Question

The three angles of a quadrilateral are 71°, 110°, 95°. Find its fourth angle.

Answer 1

A quadrilateral is a polygon with four sides
∴ Sum of interior angles
= (n - 2) x 180°
= (4 - 2) x 180°
= 2 x 180°
= 360°
Given, the three interior angles are 71°, 110°, 95°
Let the forth angle be x
∴ 71° + 110° + 95° + x = 360°
⇒ x + 276° = 360°
⇒ x
= 360° - 276°
= 84°
∴ The forth angle is 84°.