In the figure, PQST is a parallelogram and TSR is a straight line. If the area of △ △ QRS is 20cm2, find the area of the trapezium PQRT.

In the figure, PQST is a parallelogram and TSR is a straight line. If the area of $△$QRS is 20cm2, find the area of the trapezium PQRT.

Answer Details

A$△$ = $\frac{1}{2}$ x 8 x h = 20

= $\frac{1}{2}$ x 8 x h = 4h

h = $\frac{20}{4}$

= 5cm

A$△$(PQTS) = L x H

A$△$PQRT = A$△$QSR + A$△$PQTS

20 + 50 = 70cm2

ALTERNATIVE METHOD

A$△$PQRT = $\frac{1}{2}$ x 5 x 28

= 70cm2