Question

ABCD is a rectangle, AB = 4 cm, BC = 10 cm. Find the area of ΔRDC and || gm PQCD.

Answer 1

We know that,

Area of rectangle, ABCD = length × breadth

= AB × BC

= 4 × 10

= 40 cm²

If a triangle and parallelogram are drawn on the same base and between the same parallel lines, then the area of the triangle is half of the area of the parallelogram.

Since, ΔRDC and || gm ABCD are on same base DC and between same parallels DC and RQ.

∴ ar(ΔRDC) = `1/2` × ar(|| gm ABCD)

= `1/2` × 40

= 20 cm²

Parallelograms on the same base and between the same parallels are equal in area.

Since, || gm PQCD and || gm ABCD are on same base DC and between same parallels DC and RQ.

∴ ar(|| gm PQCD) = ar(|| gm ABCD) = 40 cm²