In parallelogram ABCD, DB =28 cm. AN and CM are perpendicular to BD. AN = CM =10 cm. Find the area of the parallelogram.

Answer: 280 cm
Step-by-step explanation:
The base of each of the congruent triangles ABD and CBD is BD= 28 cm. The height of each is the perpendicular 10cm.
A=(2)(bh/2) works out to A= bh since the 2/2 cancel
So 10cm × 28cm = 280cm²