Question

In the figure, if lines l and m are parallel lines, then x =

Answer 1

In the figure, l ||m

$\angle 1={70}^0$ (Corresponding angles)
In $\Delta DEF$,
Ext. $\angle 1=x+{30}^0$
$\Rightarrow {70}^0=x+{30}^0$
$\Rightarrow x={70}^0-{30}^0={40}^0$