Question

Calculate the sum of angles of a polygon with :

(i) 10 sides (ii) 12 sides (iii) 20 sides (iv) 25 sides.

Answer 1

(i) No. of sides n = 10

$\therefore$ Sum of angles of polygon$=(n-2)\times {180}^o=(10-2)\times {180}^o={1440}^o$.

(ii) no. of sides n = 12

sum of angles $=(n-2)\times {180}^o=(12-2)\times {180}^o=10\times {180}^o={1800}^o$.

(iii) $n=20$

$\therefore \text{Sum of angles of Polygon}=(n-2)\times {180}^o=(20-2)\times {180}^o\times {3240}^o$.

(iv) $n=25$

$\therefore \text{Sum of angles of polygon}=(n-2)\times {180}^o=(25-2)\times {180}^o={4140}^o$.