Question

the base angle of an isoceles triangle is 20 more than the thrice vertex angle. find the value of the equal angle​

Answer 1

Answer:

80°

Let the vertex angle be x

So, base angles are equal to 3x + 20

Also, sum of angles is equal to 180

So, x + 2(3x + 20) = 180

x + 6x + 40 = 180

7x = 140

x = 20

Since, we need to find the base angles which are equal

3x + 20 = 80