Question

In the given figure, if $△ADE\sim △ABC$, find the measure of side $BC$ in $cm$.

• A. $4.5$
• B. $3$
• C. $3.6$
• D. $2.4$

Answer 1

The correct option is C $3.6$

$AC=AE+AC=1.5+3=4.5$

$△ADE\sim △ABC\therefore \frac{AD}{AB}=\frac{DE}{BC}=\frac{AE}{AC}$

$\Rightarrow \frac{DE}{BC}=\frac{AE}{AC}\Rightarrow \frac{1.2}{x}=\frac{1.5}{4.5}\Rightarrow x=3.6cm$