Question

In an isosceles, trapezium $ABCD$, $\angle C$ is equal to:

• A. ${115}^o$
• B. ${65}^o$
• C. ${105}^o$
• D. ${75}^o$

Answer 1

The correct option is B ${65}^o$

Since, $AB\parallel DC$, the co-interior angles will be supplementary.

$\angle A+\angle D={180}^{\circ }$

$\angle D={180}^{\circ }-{115}^{\circ }$

$={65}^{\circ }$

We know that, the angles on the parallel sides are equal in an isosceles trapezium:
$⟹\angle C=\angle D={65}^{\circ }$