The value of x is 39. This triangle is an isosceles triangle. We can tell that the triangle is isosceles because when we subtract 102 from 180 we get 78 which is then divided equally into two angles of 39.
Hello! The sum of a triangle’s angles are 180 degrees. There’s 102 degree and 39 degree angle. Add those two angles. 102 + 39 = 141 degrees. 180 - 141 = 39 degrees. x = 39 degrees.
