Since there are 5 angles given, the polygon is a pentagon.
Sum of interior angles of a pentagon = (2(5) - 4) x 90° = 540°
∴\therefore∴ x + 2x + 3x + 4x + 5x = 15x
15x = 540°
x=54015=36∘x = \frac{540}{15} = 36^{\circ}x=15540=36∘
