Question

solve.... please my exam is tommo.

Answer 1

Question-(8) The sum of interior angles of a polygon is

2160. How many siedes Do this polygon have ?

Answer-(8)

Formula for such questions :

$sum \: of \: interior \: angles \: = (no \: of \: sides \: of \: polygon - 2) \times 180$

So,

$2160 = \frac{(n - 2)}{180} \\ \frac{2160}{180} = (n - 2) \\ 12 + 2 = n \\ 14 = n$

so , no of sides = 14

Question-(9) Find the number of sides of a regular polygon, whose interior

angles are as follows .

i) 140°

ii) 162°

iii) 150°

Answer-(9)

i) 140°

$140n = 180(n - 2) \\ 140n = 180n - 360 \\ 360 = 40n \\ n = 9sides$