Question

In a triangle ABC, AB=AC and ˂A=70°, find the angles,˂B and ˂C

please help !!!!!!!!!!!!!

Answer 1

Then angles
`\angle B` and
`\angle C` both measure
`55^o`

Explanation:

Notice that if sides AB and AC are equal, then the angles opposed to them (that is angle
`\angle C` and angle
`\angle B` respectively) have to be equal since equal sides oppose equal angles in a triangle.

So you also know that the addition of the three angles in a triangle must equal
`180^o`, then:

`\angle A + \angle B+\angle C= 180^o\\70^o+\angle B + \angle B = 180^o\\2\,\angle B = 180^o-70^o\\2 \angle B=110^o\\\angle B=55^o\\\angle C = 55^o`