Straight Line And Pair Of Straight Lines Ques 28
- The diagonals of a parallelogram $P Q R S$ are along the lines $x+3 y=4$ and $6 x-2 y=7$. Then, $P Q R S$ must be a
(a) rectangle
(b) square
(c) cyclic quadrilateral
(d) rhombus
$(1998,2 M)$
Show Answer
Solution:
- Slope of line $x+3 y=4$ is $-1 / 3$ and slope of line $6 x-2 y=7$ is 3 .
Here, $\quad 3 \times \frac{-1}{3}=-1$
Therefore, these two lines are perpendicular which show that both diagonals are perpendicular.
Hence, $P Q R S$ must be a rhombus.
BETA
