QRST is a parallelogram. Find x and y.

**Solution:-**

In a parallelogram opposite sites are congruent.

So

QT = RS and QR = TS

y – 4x = 9 …(1)

y = -x + 4 …(2)

substitute the value of y in the equation (1)

-x + 4 – 4x = 9 => -5x = 5 => x = -1

Put the value of x = -1 in the equaiton (2)

y = -(-1) + 4

y = 5

So the value of x = -1 and y = 5