# In an isosceles triangle, the vertex angle is twice the sum of the base angles. Find the angles of the triangle.

In a triangle ABC, let A be the vertex angle and C and B be the base angles. It is given that

B = C { it is an isosceles triangle}

And A = 2(B + C)

⇒ ∠A = 2× 2 B

A = 4 B

We know that the sum of the angles of a triangle is 180°.

4B + B + B = 180°

6B = 180 °

⇒ ∠B = 30°

So, C = B = 30°

And A = 4× B = 120°

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