Question

For the diagram given above, if $PQ$ and $CD$ are parallel to each other, then $\angle 4+\angle 5=$

• A. ${90}^{\circ }$
• B. ${180}^{\circ }$
• C. ${360}^{\circ }$

Answer 1

The correct option is B ${180}^{\circ }$

Here, $PQ$ and $CD$ are parallel to each other.
Aso, $\angle 4$ and $\angle 5$ are co-interior angles.
$\therefore$ By Co-interior angle theorem:
$\angle 4+\angle 5={180}^{\circ }$