Question

AB, BC and CD are three consecutive sides of a regular polygon. If angle BAC = 20°, find:
its each interior angle,
(ii) its each exterior angle
(iii) the number of sides in the polygon.​

Answer 1

AB, BC and CD are three consecutive sides of a regular polygon and ∠BAC=20°

,

In △BAC,AB=BC,

Therefore, ∠BCA=∠BAC=20°

(Isosceles Triangle)

Now,

∠BCA+∠BAC+∠ABC=180°

20° +20°

+∠ABC=180°

∠ABC=140 °

Each interior angle = 140 °

Hope it helps you...