Question

In figure if $DE\parallel BC$, then find the ratio of $ar.\left(△ADE\right)$ and $ar.\left(△DECB\right)$. Also , $DE=6cm,BC=12cm$.

Answer 1

Using mid point theorem, we get

$Ar\left(△ADE\right)=\frac{1}{2}Ar\left(△ABC\right)$

$2Ar\left(△ADE\right)=Ar\left(△ADE\right)+Ar\left(DECB\right)$

So, $Ar\left(△ADE\right)=Ar\left(DECB\right)$

So, $\frac{Ar\left(△ADE\right)}{Ar\left(△DECB\right)}=1$