Question

Three angles of a quadrilateral are 70^o, 120^o and 65^o. The fourth angle of the quadrilateral is :

• A. 105^o
• B. 95^o
• C. 90^o
• D. 75^o

Answer 1

The correct option is A

105^o

Sum of the four angles of a quadrilateral is 360^o.

Let x be the measure of the fourth angle.

x + 70^o + 120^o + 65^o = 360^o x + 255^o = 360^o x = 360^o - 255^o x = 105^o

So, the measure of the fourth angle is 105^o