Write down the coordinates of each of the points A, B, C, D, E shown below:
Co-ordinates of A, B, C, D and E are as follows,
A(-6 , 5 ) , B (5 , 4) , C(-3 , 2) , D (-2 , 2) , E(-1 , 4)
Draw the lines X’ OX and YOY’ as the coordinate axes on a paper and plot the following points on it.
(i)
(ii)
(iii)
(iv)
(v)
(vi)
(vii)
(viii)
On which axis do the following points lie?
(i) (7, 0)
(ii) (0, -5)
(iii) (0, 1)
(iv) (-4, 0)
(i) (7, 0) lies on X-axis.
(ii) (0, -5) lies on negative or Y-axis.
(iii) (0, 1) lies on positive Y-axis.
(iv) (-4, 0) lies on negative X-axis.
In which quadrant do the given points lie?
(i) (-6, 5)
(ii) (-3, -2)
(iii) (2, -9)
(i) In given points X co-ordinate is negative and Y co-ordinate is positive, Hence, (-6, 5) lies in 2nd quadrant.
(ii) In given points X co-ordinate is negative and Y co-ordinate is also negative, Hence, (-3, -2 ) lies in 3rd quadrant.
(iii) In given points X co-ordinate is positive and Y co-ordinate is negative, Hence, (2, -9) lies in 4th quadrant.
Draw the graph of the equation,
The given equation is y = x + 1 ……….(i)
Now,
By putting x = 0 in equation (i), we get y = 1
By putting x = 1 in equation (i), we get y = 2
By putting x = 2 in equation (i), we get y = 3
By putting x = 3 in equation (i), we get y = 4
A table is form such that:
Draw the graph of the equation,
The given equation is y = 3x + 2 …….(i)
Now,
By putting x = -1 in equation (i), we get y = -1
By putting x = 0 in equation (i), we get y = 2
By putting x = 1 in equation (i), we get y = 5
By putting x = 2 in equation (i), we get y = 8
A table is form such that:
Draw the graph of the equation,
The given equation is y = 5x - 3 …….(i)
Now,
By putting x = 0 in equation (i), we get y = -3
By putting x = 1 in equation (i), we get y = 2
By putting x = 2 in equation (i), we get y = 7
By putting x = 3 in equation (i), we get y = 12
A table is form such that :
Draw the graph of the equation,
The given equation is y = 3x …….(i)
Now,
By putting x = 0 in equation (i), we get y = 0
By putting x = 1 in equation (i), we get y = 3
By putting x = 2 in equation (i), we get y = 6
By putting x = 3 in equation (i), we get y = 9
A table is form such that:
Draw the graph of the equation,
The given equation is y = - x …….(i)
Now,
By putting x = -2 in equation (i), we get y = 2
By putting x = -1 in equation (i), we get y = 1
By putting x = 0 in equation (i), we get y = 0
By putting x = 1 in equation (i), we get y = -1
A table is form such that:
The point lies P (-5, 3) in
A. quadrant I
B. quadrant II
C. quadrant III
D. quadrant IV
We can see that, x – coordinate is negative and y- coordinate is positive.
Hence, it can be clearly said that P (-5,3) lies in the 2nd quadrant.
∴ Option B is correct
The point Q (4, -6) lies in
A. quadrant I
B. quadrant II
C. quadrant III
D. quadrant IV
We can see that, x – coordinate is positive and y- coordinate is negative.
Hence, it can be clearly said that Q (4,-6) lies in the 4th quadrant.
∴ Option D is correct.
The point Q (0, -4) lies
A. quadrant II
B. quadrant IV
C. on the x-axis
D. on the y-axis
We can see that, x – coordinate is zero and y- coordinate is negative.
Hence, it can be clearly said that Q (0,-4) lies on the y axis.
∴ Option D is correct.
The point B (8, 0) lies
A. quadrant I
B. quadrant IV
C. on the x-axis
D. on the y-axis
We can see that, x – coordinate is positive and y- coordinate is zero.
Hence, it can be clearly said that B (8,0) lies on the x axis.
∴ Option C is correct.
The point C(-6, 0) lies
A. quadrant II
B. quadrant III
C. on the x-axis
D. on the y-axis
We can see that, x – coordinate is negative and y- coordinate is zero.
Hence, it can be clearly said that C(-6,0) lies on the x axis.
∴ Option C is correct.
The point at which the two coordinate axes meet is called
A. the abscissa
B. the ordinate
C. the origin
D. the quadrant
Origin is the point of intersection of the two coordinate axes.
∴ Option C is correct.
If x > 0 and y < 0, then the point (x, y) lies in
A. quadrant I
B. quadrant II
C. quadrant III
D. quadrant IV
We have, x > 0 and y < 0
∴x is positive and y is negative
= point (x, -y) lies in 4th quadrant
∴ Option D is correct.
The points (other than the origin) for which the abscissa is equal to the ordinate lie in
A. quadrant I only
B. quadrant I and II
C. quadrant I and III
D. quadrant II and IV
We know that abscissa and ordinate can be equal in only two cases i.e.
i. x and y both are positive
ii. x and y both are negative
∴The points will lie in the 1st and 3rd quadrants only.
∴ Option C is correct.
The point in which abscissa and ordinate have different signs will the in
A. quadrant I and II
B. quadrant I and IV
C. quadrant IV and II
D. quadrant II only
We know that abscissa and ordinate can have different signs in only two cases i.e.
i. x is negative and y is positive
ii. x is positive and y is negative
∴The points will lie in the 2nd and 4th quadrants only.
∴ Option C is correct.
The perpendicular distance of the point A (7, 5) from y-axis is
A. 7 units
B. 5 units
C. 12 units
D. 2 units
Since, we have the point A (7, 5)
And we have to find its perpendicular distance from y-axis
∴The perpendicular distance will be the x- coordinate
Hence, it is 7 units.
∴ Option A if correct.
A point both of whose coordinates are negative lies in
A. quadrant I
B. quadrant II
C. quadrant III
D. quadrant IV
We have, both the coordinates are negative i.e.
x and y both are negative
Hence, the point lies in the 3rd quadrant.
∴ Option C is correct
Abscissa of a point is positive in
A. quadrant I only
B. quadrant II only
C. quadrant I and II
D. quadrant I and IV
We have, (x, y)
Where, x is positive
Hence it may lie in either 1st or 4th quadrant.
∴ Option D is correct.
The coordinates of two points are and then (abscissa of A) – (abscissa of B) = ?
A. 1
B. -1
C. 5
D. -5
Here, abscissa of A = 3
Abscissa of B = -2
According to the question,
(abscissa of A) – (abscissa of B) = 3 – (-2)
= 3 + 2 = 5
∴ Option C is correct.
The points A(2, –2), B(3, – 3), C(4, – 4) and D(5, –5) all lie in
A. quadrant II
B. quadrant III
C. quadrant IV
D. different quadrants
Let us see the plot of these points,
Since, all the given points have their x – coordinate positive and y – coordinate negative.
Hence, all these points lie in the 4th quadrant. And also they all lie in a straight line.
∴ Option C is correct
Which of the points A(0, 6), B(–2, 0), C(0, – 5) D(3, 0) and E(1, 2) does not lie on x-axis?
A. A and C
B. B and D
C. A, C and E
D. E only
We know that, a point can only lie on x-axis if its y coordinate is 0.
Hence, points A, C and E does not lie on x-axis
∴ Option C is correct
The signs of abscissa and ordinate of a point in quadrant II are respectively
A. (+, -)
B. (-, +)
C. (-, -)
D. (+, +)
Since, in the 2nd quadrant x is negative and y is positive
Hence, as per sign the point could be written as (-, +)
∴ Option B is correct.
Which of the following points does not lie on the line y = 3x + 4?
A. (1, 7)
B. (2, 10)
C. (-1, 1)
D. (4, 12)
We have,
y = 3x + 4 (i)
a. (1, 7) [putting x = 1 and y = 7 in (i)]
7 = 3(1) + 4
7 = 7
Thus, A lies on the line.
b. (2, 10) [putting x = 2 and y = 10 in (i)]
10 = 3(2) + 4
10 = 10
Thus, B lies on the line.
c. (-1, 1) [putting x = -1 and y = 1 in (i)]
1 = 3(-1) + 4
1 = 1
Thus, C lie on the line.
d. (4, 12) [putting x = 4 and y = 12 in (i)]
12 = 3(4) + 4
12 ≠ 16
Thus, D does not lie on the line.
∴ Option D is correct
Which of the following points lies on the line y = 2x + 3?
A. (2, 8)
B. (3, 9)
C. (4, 12)
D. (5, 15)
We have, y = 2x + 3 (i)
a. (2, 8) [putting x = 2 and y = 8 in (i)]
8 = 2(2) + 3
8 ≠ 7
Thus, A doesn’t lie on the line.
b. (3, 9) [putting x = 3 and y = 9 in (i)]
9 = 2(3) + 3
9 = 9
Thus, B lies on the line.
∴ Option B is correct.
If a < 0 and b < 0, then the point P(a, b) lies in
A. quadrant IV
B. quadrant II
C. quadrant III
D. quadrant I
We have, a < 0 and b < 0
i.e. both x and y are negative
Hence, point P lies in 3rd quadrant
∴ Option C is correct.
The perpendicular distance of the point P(4, 3) from the y-axis is
A. 3 units
B. 4 units
C. 5 units
D. 7 units
Since, we have the point P (4, 3)
And we have to find its perpendicular distance from y-axis
∴The perpendicular distance will be the x- coordinate
Hence, it is 4 units.
∴ Option B is correct
The area of the ΔOAB with O(0, 0), A(4, 0) and B(0, 6) is
A. 8 sq units
B. 12 sq units
C. 16 sq units
D. 24 sq units
Here, OA = 4 – 0 = 4 units
OB = 6 – 0 = 6 units
= 12 sq. units
∴ Option B is correct.
The area of the ΔOPQ with O(0, 0), P(1, 0) and Q(0, 1) is
A. 1 sq unit
B. sq unit
C. sq unit
D. 2 sq units
Here, OA = 4 – 0 = 4 units
OB = 6 – 0 = 6 units
= 12 sq. units
∴ Option B is correct
Consider the three statements given below:
I. Any point on x-axis is of the form
II. Any point on y-axis is of the form
III. The point lies on both the axes.
Which is true?
A. I and II
B. I and III
C. II and III
D. III only
Here,
1st statement is true as the point lying on x axis has its y coordinate as 0
2nd statement is true as the point lying on y axis has its x coordinate as 0
3rd statement is false as a point can never lie on both the axes unless it is their point of intersection i.e. (0, 0)
∴ Option A is correct
The question consists of two statements, namely, Assertion (A) and Reason (R). Please select the correct answer.
A. Both Assertion (A) and Reason (R) are true and Reason (R) is a correct explanation of Assertion (A).
B. Both Assertion (A) and Reason (R) are true but Reason (R) is not a correct explanation of Assertion (A).
C. Assertion (A) is true and Reason (R) is false.
D. Assertion (A) is false and Reason (R) is true.
We have, pb(-3, 0)
Since, the y coordinate is 0.
Hence, it lies on x-axis.
∴ Option (a) is correct.
The question consists of two statements, namely, Assertion (A) and Reason (R). Please select the correct answer.
A. Both Assertion (A) and Reason (R) are true and Reason (R) is a correct explanation of Assertion (A).
B. Both Assertion (A) and Reason (R) are true but Reason (R) is not a correct explanation of Assertion (A).
C. Assertion (A) is true and Reason (R) is false.
D. Assertion (A) is false and Reason (R) is true.
We have,
Point O(0, 0)
It does not lie in any of the quadrant because it is the point of intersection of both the axes.
∴ Option (d) is the correct option.
The question consists of two statements, namely, Assertion (A) and Reason (R). Please select the correct answer.
A. Both Assertion (A) and Reason (R) are true and Reason (R) is a correct explanation of Assertion (A).
B. Both Assertion (A) and Reason (R) are true but Reason (R) is not a correct explanation of Assertion (A).
C. Assertion (A) is true and Reason (R) is false.
D. Assertion (A) is false and Reason (R) is true.
We know that,
The point P (-6, -4) lies in the third quadrant as the points of the type (-, -) lie in III quadrant
Also, we know that
The signs of points in quadrants I, II, III and IV are respectively (+,+) (-,+) (-,-) and (+,-)
∴ Both assertion and reason are true and reason justifies the assertion
Hence, option (a) is correct
The question consists of two statements, namely, Assertion (A) and Reason (R). Please select the correct answer.
A. Both Assertion (A) and Reason (R) are true and Reason (R) is a correct explanation of Assertion (A).
B. Both Assertion (A) and Reason (R) are true but Reason (R) is not a correct explanation of Assertion (A).
C. Assertion (A) is true and Reason (R) is false.
D. Assertion (A) is false and Reason (R) is true.
According to question,
If a b then (a, b) (b, a)
This statement is true
Also, (4, -3) lies in the quadrant IV
As both assertion and reason are true but the reason does not justify the assertion
Hence, option (b) is correct
Write whether the following statements are true or false?
(i) The point lies in the quadrant I.
(ii) The perpendicular distance of the point from x-axis is 5 units.
(i) The given statement is false as the ordinate of the point P (6, 0) is 0 and hence it lies on the x-axis
(ii) The given statement is also false because the perpendicular distance of the point A (5, 4) from the x-axis will be 4 units instead of 5 units
State whether true or false:
(i) The mirror image of the point in the x-axis is
(ii) The mirror image of the point in the y-axis is
(i) The given statement is false because the mirror image of the point A (4, 5) on the x-axis is A’ (4, 5) instead of A’ (-4, 5)
(ii) The given statement is true as the mirror image of the point A (4, 5) in the y-axis is A’ (-4, 5)
Write whether the following statements are true or false:
A. The point (-5, 0) lies on x-axis.
B. The point (0, -3) lies in quadrant II.
A. The given statement is true as the ordinate of the point is 0 which lies on the x-axis
B. The given statement is false as the point (0, -3) lies on the y-axis
Match the following columns:
The correct answer is:
A. -…….., B. -…….,
C. -…….., D. -…….,
(a) We know that,
The points that lie on the x-axis have coordinate = 0
∴ The equation of the x-axis will be y = 0
(b) We know that,
The points that lie on the y-axis have abscissa = 0
∴ The equation of the y-axis will be x = 0
(c) We know that,
Any point on the x-axis is of the form (a, 0)
(d) We also know that,
A point on the y-axis is of the form = (0, b)
Hence the correct match for the given table is as follows:
(a) – (q)
(b) – (s)
(c) - (p)
(d) – (r)
Match the following columns:
The correct answer is:
A. -…….., B. -…….,
C. -…….., D. -…….,
(a) We know that,
The point of the type (a, 0) lies on the x-axis
∴ Point A (-3, 0) lies on the x-axis
(b) We know that,
The point of the type (-, -) lie in the III quadrant
∴ Point B (-5, -1) lies in the quadrant III
(c) We know that,
The point of the type (+, -) lie in the quadrant IV
∴ Point C (2, -3) lies in the quadrant IV
(d) We know that,
The point of the type (o, b) lies on the y-axis
∴ Point D (0, -6) lies on the y-axis
Hence, the correct match for the above given table is as follows:
(a) - (s)
(b) – (r)
(c) – (q)
(d) – (p)
Without plotting the given points on a graph paper indicate the quadrants in which they lie, if
A) ordinate = 6, abscissa = - 3
B) ordinate = 6, abscissa = 4
C) abscissa = -5, ordinate = -7
D) ordinate = 3, abscissa = 5
A. We know that,
Point (-3, 6) lie in the second quadrant
B. We know that,
Point (4, -6) lie in the fourth quadrant
C. We know that,
Point (-5, -7) lie in the third quadrant
D. We know that,
Point (5, 3) lie in the first quadrant
Plot the point P(–6, 6) on a graph paper. Draw PL ⊥ x-axis and PM ⊥ y-axis. Write the coordinates of L and M.
The required point is shown in the graph given below:
In the above graph PL is drawn perpendicular to x-axis while PM is drawn perpendicular to y-axis
∴ Coordinates of L = (-6, 0)
Also, coordinates of M = (0, 3)
Plot the points A(–5, 2), B(3, –2), C(–4, –3) and D(6, 0) on a graph paper.
The given four points A (-5, 2), B (3, -2), C (-4, -3) and D (6, 0) are plotted on the graph paper as follows:
The three vertices of ΔABC are A(1, 4), B(–2, 2) and C(3, 2). Plot these points on a graph paper and calculate the area of ΔABC.
Let the vertices of the triangle be A (1, 4), B (-2, 2) and C (3, 2)
Now, when we plot and join these points on the graph paper, we get a triangle ABC
Let the line BC intersect y-axis at D
∴ BC = BD + DC
= (2 + 3) units
= 5 units
Now, AL is drawn perpendicular to x-axis meeting BC at L
∴ Ordinate of point L = Ordinate of point C – 2
AL = AM – LM
= 4 – 2
= 2 units
Hence, area of =
=
=
= 5 units
∴ Area of the triangle ABC = 5 square units
The three vertices of a rectangle ABCD are A(2, 2), B(–3, 2) and C(–3, 5). Plot these points on a graph paper and find the coordinates of D. Also, find the area of rectangle ABCD.
Let the three vertices of rectangle ABCD be A (2, 2), B (-3, 2) and C (-3, 5)
Now, on plotting these points on the graph paper and by joining the points we get:
The point A lies in the first quadrant while B and C lie in the second quadrant
Let us assume D be the fourth vertex of the rectangle
∴ Abscissa of D = Abscissa of A = 2
And, Ordinate of D = Ordinate of C = 3
Hence, Coordinate of the fourth vertex, D = (2, 5)
Let y-axis cut AB and CD at point L and M respectively
∴ AB = (BL + LA)
= (3 + 2)
= 5 units
Also, BC = 5 – 2
= 3 units
∴ Area of rectangle ABCD = BC × AB
= 3 × 5
= 15 square units
Hence, the area of the rectangle ABCD is 15 square units
The three vertices of a rectangle ABCD are A(3, 2), B(–2, 2) and C(3, –3). Plot these points on a graph paper and find the coordinates of D. Also, find the area of rectangle ABCD.
Let the three vertices of rectangle ABCD be A (3, 2), B (-2, 2) and D (3, -3)
Now, on plotting these points on the graph paper and by joining the points we get:
A, B and D lie in different quadrants
Let us assume D be the fourth vertex of the rectangle
∴ Abscissa of C = Abscissa of B = - 2
And, Ordinate of C = Ordinate of D = - 3
Hence, Coordinate of the fourth vertex, C = (-2, -3)
Let y-axis cut AB and CD at point L and M respectively
∴ AB = (BL + LA)
= (2 + 3)
= 5 units
∴ Area of rectangle ABCD = AB × AB
= 5 × 5
= 25 square units
Hence, the area of the rectangle ABCD is 25 square units
From the figure given below write each of the following:
(i) The coordinates of point D
(ii) The abscissa of the point A
(iii) The point whose coordinates are (2,-3)
(iv) The point whose coordinates are (-3,-4)
(v) The ordinate of point E
(vi) The coordinates of B
(vii)The coordinates of F
(viii)The coordinates of the origin
(i) We have,
Abscissa of point D = 0
Ordinate of point D = -5
∴ Coordinates of point D = (0, -5)
(ii) From the given graph, we have:
Abscissa of point A = - 4
(iii) From the given graph, we have:
Coordinates of point E = (2, -3)
(iv) From the given graph, we have:
Coordinates of point C = (-3, -4)
(v) From the given graph, we have:
Ordinate of point E = - 3
(vi) From the given graph, we have:
Point B lies on x-axis
∴ Abscissa of point B = - 2
Ordinate of point B = 0
Hence coordinates of point B are (-2, 0)
(vii) From the given graph, we have:
Abscissa of point F = 5
Ordinate of point F = - 1
(viii) From the given graph, we have:
Coordinates of the origin = (0, 0)
If x < 0 and y > 0, then the point (x, y) lies in
A. quadrant I
B. quadrant II
C. quadrant III
D. quadrant IV
According to question, we have
x < 0 and y > 0 then these points will lie in second quadrant
As, points of the type (-, +) lie on the second quadrant
∴ Option B is correct
Which point does not lie in any quadrant?
A. (3, -6)
B. (-3, 4)
C. (5, 7)
D. (0, 3)
From the given options in the question the point which does not lie in any quadrant is (0, 3)
∴ Option D is correct
The area of ΔAOB having vertices A( 0,6) , O( 0,0) and B( 6,0) is
A. 12 sq units
B. 36 sq units
C. 18 sq units
D. 24 sq units
When we plot the given points in the graph paper then,
is the right angle triangle, where
OB = Base = 6 units
Height of triangle = OA = 6 units
∴ Area of =
=
=
= 18 square units
∴ Option C is correct
Read the statements given below and choose the correct answer:
I. Any point on x-axis is of the form for all
II. Any point on y-axis is of the form for all
III. Any point on both the axes is of the form for all and
Which of the following is true?
A. I and II
B. I and III
C. I only
D. III only
We know that,
Any point which lies on the x-axis is of the form (x, 0) for x
Also, point which lies on the y-axis is of the form (0, y) for y
Hence, statement I and II are true
∴ Option A is correct
Which of the following points does not lie on the line 3y = 2x – 5?
A. (7, 3)
B. (1, -1)
C. (-2, -3)
D. (-5, 5)
From the given four options, (-5, 5) does not satisfy the given equation:
3x = 2x – 5
We have,
R.H.S = 2 × (-5) – 5
= - 10 – 5
= - 15
Also, L.H.S = 3 × 5
= 15
Hence, the point (-5, 5) does not lie on the line 3y = 2x – 5
∴ Option D is correct
Plot each of the following points on a graph paper:
A(3, –5), B(–5, –2), C(–6, 1) and D(4, 0).
The following given points are plotted on the graph paper as follows:
If 2y = 3 – 5x, find the value of y when x = –1.
We have,
2y = 3 – 5x
Now, by putting the value of x = - 1 in the given equation we get:
2y = 3 – 5 × (-1)
2y = 3 + 5
2y = 8
y = = 4
Hence, when x = - 1 then y = 4
On which axis does the point A(0, –4) lie?
We have,
Abscissa of point A (0, -4) = 0
∴ Point A lies on the y-axis
In which quadrant does the point B(–3, –5) lie?
From the given point given in the question, we have
The abscissa and the ordinate of the point B (-3, -5) are negative and we know that those points lie on the III quadrant
∴ Point B lies in the third quadrant
What is the perpendicular distance of the point P(–2, –3) from the y-axis?
We have,
Abscissa of point P (-2, -3) = - 2
We know that, distance cannot be negative
∴ The perpendicular distance of the given point from the y-axis is 2 units
At what point do the coordinate axes meet?
The coordinate axes meet at the origin i.e., at point O (0, 0)
For each of the following write true or false:
(i) The point lies in quadrant I.
(ii) The ordinate of a point is -3 and its abscissa is -4. The point is
(iii) The points and both lie in quadrant IV.
(iv) A point lies on y-axis at a distance of 3 units from x-axis. Its coordinates are (3, 0).
(v) The point lies on y-axis.
(vi) The point lies on x-axis as well as y-axis.
(i) The given statement is false as the given point lies on the x-axis
(ii) The given statement is also false as the point is P (-4, -3)
(iii) The given statement is also false as the point A (1, -1) lies in the quadrant IV and point B (-1, 1) lies in the quadrant II
(iv) The given statement is false as the coordinates of the point are (0, 3)
(v) The given statement is true as the point C (0, -5) lies on y-axis
(vi) The given statement is also true as the point O (0, 0) lies on x-axis as well as y-axis
Taking a suitable scale, plot the following points on a graph paper:
The concept is:
(-x, +y) 2nd Quadrant
(-x, -y) 3rd Quadrant
(+x, -y) 4th Quadrant
The given points are plotted as follows:
Read the graph paper given below and answer the following:
(i) Write the points whose ordinate is 0.
(ii) Write the points whose abscissa is 0.
(iii) Write the points whose ordinate is -3.
(iv) Write the points whose abscissa is 2.
(v) Write the coordinates of all points in quadrant II.
(vi) Write the coordinates of all those points for which abscissa and ordinate have the same value.
(i)The given four points G (-3, 0) , H (-8, 0), Q (4, 0) and R (9, 0) lie on the x-axis
∴ Their ordinates are equal to O
(ii) The given four points L (0, -6) , K (0, -2), D (0, 3) and C (0, 7) lie on the x-axis
∴ Their abscissa are equal to O
(iii) The ordinates of points M (-1, 3) , J (-4, -3) and P (6, 3) are equal to -3
(iv) Points having abscissa equal to 2 is B (2, 4) and N (2, -1)
(v) From the given points, points E and F lie in quadrant II
∴ Coordinates of E = (-4, 4)
Coordinates of F = (-6, 2)
(vi) Coordinates of all those points having abscissa and ordinate same value are:
A (3, 3) and I (-2, -2)
(i) Write the mirror image of the point
(2, 5) in the x-axis.
(ii) Write the mirror image of the point
(3, 6) in the y-axis.
(iii) A point (a, b) lies in quadrant II. In which quadrant does (b, a) lie?
(i) The mirror image of the point (2, 5) in the x-axis is (2, -5)
(ii) The mirror image of the point (3, 6) in the y-axis is (-3, 6)
(iii) According to question,
Point (a, b) lies in the second quadrant so a must be a negative number and b must be a positive number
∴ Point (b, a) lies in the fourth quadrant
Without plotting the points on a graph paper indicate the quadrant in which they lie:
(i) ordinate = 4, abscissa = - 3
(ii) ordinate = - 5, abscissa = 4
(iii) abscissa = -1, ordinate = -2
(iv) abscissa = -5, ordinate = 3
(v) abscissa = 2, ordinate = 1
(vi) abscissa = 7, ordinate = -4
The concept is:
(+x, +y) 1st Quadrant
(-x, +y) 2nd Quadrant
(-x, -y) 3rd Quadrant
(+x, -y) 4th Quadrant
(i) Points having ordinate = 4 and abscissa = - 3 lies in the quadrant II
(ii) Points having ordinate = - 5 and abscissa = 4 lies in the quadrant IV
(iii) Points having ordinate = - 2 and abscissa = - 1 lies in the quadrant III
(iv) Points having ordinate = 3 and abscissa = - 5 lies in the quadrant II
(v) Points having ordinate = 1 and abscissa = 2 lies in the quadrant I
(vi) Points having ordinate = - 4 and abscissa = 7 lies in the quadrant IV
Which of the following points do not lie on x-axis?
(i) A(0, 6) (ii) B(2, 0)
(iii) C(0, –2) (iv) D(–6, 0)
(v) E(2, 1) (vi) F(0, 4)
From the points given in the question, we have
Points B (2, 0) and D (6, 0) have their ordinates = 0
∴ They lie on the point x-axis
And the point whose ordinate is not equal to zero does not lie on the x-axis
∴ Points A, C, E and F do not lie on the x –axis
Three vertices of a rectangle ABCD are A(3, 1), B(–3, 1) and C(–3, 3). Plot these points on a graph paper and find the coordinates of the fourth vertex D.
Let the three vertices of rectangle ABCD be A (3, 1), B (-3, 1) and C (-3, 3)
Now, on plotting these points on the graph paper and by joining the points we get:
A lies in thye first quadrant while B and C lie in the second quadrant
Let us assume D be the fourth vertex of the rectangle
∴ Abscissa of D = Abscissa of A = 3
And, Ordinate of D = Ordinate of C = 3
Hence, Coordinate of the fourth vertex, D = (3, 3)
Write the coordinates of vertices of a rectangle OABC, where O is the origin, length OA = 5 units lying along x-axis, breadth AB = 3 units and B lying in the fourth quadrant.
It is given in the question that,
OABC is a rectangle where O is the origin and OA = 5 units along x-axis
Also, AB = 3 units and B lies in the fourth quadrant
Now, coordinates of origin, O = (0, 0)
As point A lies on the x-axis
∴ Coordinate of point A = (5, 0)
Also, point B lies in the fourth quadrant
So, coordinate of point B will be negative
As the given width AB = 3 units
∴ Coordinates of point B = (5, -3)
Also, point C and O lies on the same line
Thus, abscissa of C = abscissa of O = 0
Similarly, Point C and B lies on the same altitude
Hence, both points have equal altitude
∴ Coordinates of C = (0, -3)
Hence, the coordinates of the vertices of the given rectangle are:
O (0, 0), A (5, 0), B (5, -3) and C (0, -3)
Plot the points A(2, 5), B(–2, 2) and C(4, 2) on a graph paper. Join AB, BC and AC. Calculate the area of ΔABC.
Let the three vertices of triangle ABC be:
A (2, 5), B (-2, 2) and C (4, 2)
Now, when we plot these points in the graph paper then we see that,
Point A and C lie in the quadrant I and point B lie in the II quadrant
Let the line BC intersect y-axis at point D
∴ BC = (BD + DC)
= (2 + 4) units
= 6 units
Now, we have to draw AM perpendicular to x-axis and intersect BC at L
∴ Ordinate of point L = Ordinate of point B - Ordinate of point C
AL = AM – LM
= 5 – 2
= 3 units
Hence, Area of triangle ABC =
=
=
= 9 square units
∴ Area of triangle ABC = 9 square units