Question

Given area of parallelogram $ABCD$ is $100m^2.$ Find $DC$, if $BH=10m,BH\perp DC$.

• A. $5m$
• B. $15m$
• C. $10m$
• D. $20m$

Answer 1

Answer: (C)

$10m$

$ar\left(BCD\right)=\frac{1}{2}ar\left(ABCD\right)$
$\Rightarrow \frac{1}{2}\times DC\times BH=\frac{1}{2}\times 100$
$\Rightarrow \frac{1}{2}\times DC\times 10=50$
$\Rightarrow DC=10m$