Find the angle of an isosceles triangle if its apex angle is 51 degrees greater than its base angle.

Since the triangle is isosceles, its angles at the base are equal to each other.

Let’s denote the angle at the base through X.

Then the angle at the apex of the triangle will be (X + 51).

The sum of all the angles of the triangle is 180.

X + X + (X + 51) = 180.

3 x X = 180 – 51.

X = 129/3 = 43.

The base angles are 43.

Then the angle at the vertex is 43 + 51 = 94.

Answer: The apex angle is 94, the base angles are 43.