Question

In the figure given below, find $x$ if AB || CD.

Answer 1

From the given figure,
$\angle FEC+\angle ECD=180°\angle ECD={180}^{\circ }-{150}^{\circ }={30}^{\circ }$
$\text{(Sum of interior angles on the same}\text{side of the transversal is 180°)}$

$\angle ABC=\angle BCD\left(\text{Alternate interior angles}\right)$

$\Rightarrow x={25}^{\circ }+\angle ECD\Rightarrow x={25}^{\circ }+{30}^{\circ }={55}^{\circ }$