Question

In an isosceles triangle the base angles are equal and the vertex angle is twice of each base angle .Find the measures of the angles of the triangle.

45⁰,45⁰,90⁰

80⁰,80⁰,100⁰

50⁰,50⁰,80⁰

None of these​

Answer 1

Given :-

• In an isosceles triangle the base angles are equal and the vertex angle is twice of each base angle.

To Find :-

• Measures of the angles of the triangle.

Solution :-

We know that,

An isosceles triangle has two equal sides of equal length.

Let the angles of the triangle be 'x' and the bigger angles be '2x'

Sum of all angles in a triangle = 180°

So,

2x + x + x = 180°

4x = 180°

x = 180/4

x = 45°

So the two equal angles of of the isosceles triangles = 45°

∴ The angle twice of the base angle = 45° × 2 = 90°

Hence, The angles of the isosceles triangles are ⇒ 45°, 45°, 90°