Question

Each equal angle of an isosceles triangle is less than the third angle by 15°. Find the angles.

Answer 1

Let equal angles of the isosceles triangle be x each. Therefore, non-equal angle = x + 15°
Angles of a triangle = 180°
x + x + (x + 15°) = 180°
3x + 15° = 180°
3x = 165°
x = 55°
x  + 15 = 70°
Angles are 55°, 55° and 70°.