Question

Given $△ABC\cong △QRP$
If, $\angle A=\angle Q={60}^{\circ }\text{and}\angle R={40}^{\circ }$,then $\angle C$ measures .

• A. 80°
• B. 60°
• C. 100°

Answer 1

The correct option is A 80°

Given,
$△ABC\cong △QRP$

Corresponding parts of congruent triangles are equal.So,
$\angle A=\angle Q=60°$ ..... (Given)
$\angle B=\angle R=40°$ .... (Corresponding parts)
$\angle C=\angle P$ ..... (Corresponding parts)
We know that, sum of all the internal angles of a triangle is equal to 180°.

So, in $△ABC$,
$\angle A+\angle B+\angle C=180°$
$\Rightarrow \angle C=180°-(60°+40°)$
$\Rightarrow \angle C=80°$