Question

 If the vertical angle of an isosceles triangle is 100° then find the measures of its base angles.

Answer 1

Let the measure of each of the base angles be x°.

By the condition,

x + x + 100 = 180° [ Angle sum property of a triangle]

⇒ 2x + 100 = 180

⇒ 2x = 180 – 100 = 80

⇒ x = 40

∴ The measure of each of the base angles of the triangle is 40°.

Answer 2

Answer:

Answer. the base angle will be (180° - 100°) = 80°.