Question

In the given figure $\angle 1={60}^o$ and $m$ and $n$ are parallel. Find $\angle 6$.

Answer 1

Given $\angle 1={60}^0$ vertically opposite angle

$\angle 1=\angle 3={60}^0$

$\angle 3+\angle 6={180}^0$ supplementary angle

$\Rightarrow \angle 6={180}^0-{60}^0={120}^0$.