A pentagon has four of its angles equal. If the size of the fifth angle…

A pentagon has four of its angles equal. If the size of the fifth angle is 60^o, Find the size of each of the four equal angles.

Correct Answer: Option C

Explanation

The sum of interior angle of pentagon
(5 sides) = (2n – 4) x 90^o
n = 5
(2 x 5 – 4) x 90^o = 6 x 90^o
= 540^o
540^o – 60^o = 480^o (div) 4
= 120^o