Question

In the given figure, find the value of $x$, if $DE\parallel BC$.

Answer 1

From the given figure, we know that:

$\Delta ADE$ and $\Delta ABC$ are similar triangles.

Using mid point theorem:

$\frac{AD}{DB}=\frac{AE}{EC}=\frac{DE}{BC}$

Substituting the value of lengths from the given figure.

$\frac{3}{6}=\frac{3.5}{7}=\frac{4.5}{x}$

$\frac{1}{2}=\frac{1}{2}=\frac{4.5}{x}$

$x=9$

Hence, this is the answer.