Question

In $\Delta ABC,AB=ACand\angle B=\frac{\angle A}{2}$ what type of triangle is $\Delta ABC$?

• A. Equilateral triangle
• B. Acute-angled triangle`
• C. Right-angled triangle
• D. Obtuse-angled triangle

Answer 1

The correct option is C Right-angled triangle

R.E.F image

$\angle B=\angle C=\frac{\angle A}{2}$

(isosceles $\Delta$)

$\angle A+\angle B+\angle C={180}^{\circ }$

$\angle A+\frac{\angle A}{2}+\frac{\angle A}{2}={180}^{\circ }$

$\angle A={90}^{\circ }$

$\therefore \left(C\right)$ Ans