Question

In a $$\bigtriangleup ABC , AB = AC $$ and $$ | A = 50^{\circ} $$ find $$\angle B $$ and $$ \angle C $$

Answer 1

$$ \angle A + \angle B +\angle C = 180^{\circ}$$
(Sum of the angle of a triangle is $$180^{\circ}$$)
$$ 50 + \angle B + \angle B = 180^{\circ}$$
$$\because \angle B = \angle C $$ Base angles of an isosceles triangle
$$ 50 + 2 \angle B = 180^{\circ}$$
$$2 \angle B =- 180 - 50$$
$$2 \angle B = 130^{\circ}$$
$$ \angle B = \dfrac{130}{2}$$
$$\angle B = 65^{\circ}$$
$$ \angle B = \angle C = 65^{\circ}$$