Question

In the given figure, ABC is an isosceles tringle with AB=AC and $\angle A={50}^{\circ }$, $\angle B$ is equals to:

• A. ${50}^{\circ }$
• B. ${65}^{\circ }$
• C. ${90}^{\circ }$
• D. ${130}^{\circ }$

Answer 1

The correct option is B ${65}^{\circ }$

$AB=SC$

$\Rightarrow \angle B=\angle C$ (As angles opposite to equal sides are equal)

Let it be $x$

using angle sum property of triangle

$\angle A+\angle B+\angle C={180}^{\circ }\Rightarrow {50}^{\circ }+x+x={180}^{\circ }\Rightarrow 2x={130}^{\circ }\Rightarrow x={65}^{\circ }$

So $\angle B={65}^{\circ }$