Question

one base angle of isosceles triangle is 65°.find its angle of vertex​

Answer 1

Answer:

since in an isosceles triangle the two sides are equal then

★the angles opposite to equal sides are equal.(angle A=B)

→angle A+B+C =180(angle sum property)

A+A+C=180

2A+C=180

2×65+C =180

C=180-130

C=50°

Answer 2

Vertex angle is 50° if one base angle of isosceles triangle is 65°

Given:

One base angle of isosceles triangle is 65°

To Find:

Vertex angle

Solution:

Isosceles triangle have 2 Equal sides.

Angles opposite to equal sides are equal in measure.

Both Base angles of an isosceles triangle are of Equal measure

one base angle = 65°

=> Another base angle = 65°

Assume that Vertex angle = x°

Sum of all the angles of a triangle is 180°

=> 65° + 65° + x° = 180°

=> 130° + x° = 180°

=> x° = 50°

Vertex angle = 50°