Advertisements
Advertisements
Question
If P(2, 4), Q(0, 3), R(3, 6) and S(5, y) are the vertices of a parallelogram PQRS, then the value of y is
Options
7
5
-7
-8
Solution
It is given that P(2, 4), Q(0, 3), R(3, 6) and S(5, y) are the vertices of a parallelogram PQRS.
Join PR and QS, intersecting each other at O.
We know that the diagonals of the parallelogram bisect each other. So, O is the mid-point of PR and QS.
Coordinates of mid-point of PR = \[\left( \frac{2 + 3}{2}, \frac{4 + 6}{2} \right) = \left( \frac{5}{2}, \frac{10}{2} \right) = \left( \frac{5}{2}, 5 \right)\]
Coordinates of mid-point of QS = \[\left( \frac{0 + 5}{2}, \frac{3 + y}{2} \right) = \left( \frac{5}{2}, \frac{3 + y}{2} \right)\]
Now, these points coincides at the point O.
\[\therefore \left( \frac{5}{2}, \frac{3 + y}{2} \right) = \left( \frac{5}{2}, 5 \right)\]
\[ \Rightarrow \frac{3 + y}{2} = 5\]
\[ \Rightarrow 3 + y = 10\]
\[ \Rightarrow y = 7\]
Thus, the value of y is 7.
APPEARS IN
RELATED QUESTIONS
On which axis do the following points lie?
S(0,5)
Find the coordinates of the circumcentre of the triangle whose vertices are (3, 0), (-1, -6) and (4, -1). Also, find its circumradius.
In the seating arrangement of desks in a classroom three students Rohini, Sandhya and Bina are seated at A(3, 1), B(6, 4), and C(8, 6). Do you think they are seated in a line?
In what ratio is the line segment joining the points (-2,-3) and (3, 7) divided by the y-axis? Also, find the coordinates of the point of division.
The line segment joining the points A(3,−4) and B(1,2) is trisected at the points P(p,−2) and Q `(5/3,q)`. Find the values of p and q.
If the point `P (1/2,y)` lies on the line segment joining the points A(3, -5) and B(-7, 9) then find the ratio in which P divides AB. Also, find the value of y.
Find the coordinates of the circumcentre of a triangle whose vertices are (–3, 1), (0, –2) and (1, 3).
Mark the correct alternative in each of the following:
The point of intersect of the coordinate axes is
A point whose abscissa and ordinate are 2 and −5 respectively, lies in
If the point \[C \left( - 1, 2 \right)\] divides internally the line segment joining the points A (2, 5) and B( x, y ) in the ratio 3 : 4 , find the value of x2 + y2 .
What is the distance between the points (5 sin 60°, 0) and (0, 5 sin 30°)?
What is the distance between the points \[A\left( \sin\theta - \cos\theta, 0 \right)\] and \[B\left( 0, \sin\theta + \cos\theta \right)\] ?
If the points A (1,2) , O (0,0) and C (a,b) are collinear , then find a : b.
The distance between the points (cos θ, 0) and (sin θ − cos θ) is
The coordinates of the point on X-axis which are equidistant from the points (−3, 4) and (2, 5) are
The distance of the point (4, 7) from the x-axis is
The ratio in which the line segment joining P (x1, y1) and Q (x2, y2) is divided by x-axis is
If the sum of X-coordinates of the vertices of a triangle is 12 and the sum of Y-coordinates is 9, then the coordinates of centroid are ______
A point both of whose coordinates are negative will lie in ______.
The distance of the point (–1, 7) from x-axis is ______.