Question

allengers
In the adjacent figure, all the angles marked with a dot
are equal. Find the measure of angle ABC.
1) 30°
2) 36°
3) 45°
4) 48°​

Answer 1

in triangle prq ,

x+x+angle prq = 180

therefore angle prq = 180-2x

now ,

angle prq = angle arc (vertical opposite angles)

therefore angle arc = 180-2x

in triangle arc

a+b+180-2x=180

a+b=2x

now in traingle abc

a+b+3x = 180

2x+3x=180

5x=180

x=36