Question

If ABDE is a parallelogram with all four sides equal, then find the area of ABDE given that its perimeter is 40 cm and AC = 15cm.

• A. $75{\text{cm}}^2$
• B. $150{\text{cm}}^2$
• C. $300{\text{cm}}^2$
• D. $600{\text{cm}}^2$

Answer 1

The correct option is B $150{\text{cm}}^2$

As all sides of the given parallelogram are known to be equal, each side thus measures one-fourth of the perimeter.
$⟹$ BD = $\frac{40}{4}$ = 10 cm
Area of parallelogram = base $\times$ height
= BD$\times$AC
= 10 $\times$ 15
= $150{\text{cm}}^2$