Q. 34.5( 15 Votes )

# If the vertex angle of an isosceles triangle is 50°, find the other angles.

Answer :

Given: vertex angle

let ∠A = 55°

in an isosceles triangle opposite angles of opposite sides are equal.

Hence,

Let ∠B = ∠ C = x

As we know, using theorem (1), in any triangle, sum of the three interior angles is 180 °.

So,

∠A + ∠B + ∠ C = 180°

⇒ 50° + x + x = 180°

⇒ 2x = 180° - 50°

⇒ 2x = 130°

⇒ x = 65°

So, ∠B = ∠ C = 65°.

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