Question

In an isosceles triangle the base angles are equal, the vertex angle is 40°, then the base angle of
the triangle is ____ degree.

Answer 1

Answer:

45

Step-by-step explanation:

Answer 2

Answer:

• The base angles of the triangle is 140/2 = 70° each

Step-by-step explanation:

Let x be the base angle of an isosceles triangle.

It is given that the base angle of an isosceles triangle are equal and the vertex angle of an isosceles triangle is 40°

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

x + x + 40° = 180°

2x + 40° = 180°

2x = 180° - 40°

2x = 140°

Dividing both sides by 2, we get

$\boxed{\pink{x = 70}}$

Hence, the base angle of the isosceles triangle is 70° , 70°