Question:
Mark (✓) against the correct answer:
Each interior angle of a polygon is 135. How many sides does it have?
(a) 10
(b) 8
(c) 6
(d) 5
Solution:
(b) 8
Interior angle $=\frac{180(n-2)}{n}$
$\Rightarrow 135=\frac{180(n-2)}{n}$
$\Rightarrow 135 n=180 n-360$
$\Rightarrow 360=180 n-135 n$
$\Rightarrow n=8$
It has 8 sides.