Question

Refer to the figure: DE is parallel to BC.

$Find\frac{AD}{DB}$.

Answer 1

Consider$△ADE$ and $△ABC$

$\angle DAE=\angle BAC$ [Common angle]

$\angle ADE=\angle ABC$ [right angle]

Therefore by AA similarity criterion, the triangles$△ADE$ and $△ABC$ are similar.

So, $\frac{AD}{AB}$ = $\frac{AE}{AC}$ (By B.P.T)

$⟹$ $\frac{AD}{DB}$ = $\frac{AE}{EC}$