What is the measure of one interior angle?

Answer 1

sum of external angles of a polygon is always 360°

sum of 10 external angles = 360°

each exterior angle = 360/10 = 36°

exterior angle and interior angle forms a linear pair i.e. = 180°

interior angle = 180 - 36 = 144°

sum of exterior angles of polygon is

= (n - 2) × 180°

= (10 - 2) × 180

= 1440°

so each interior angle = 1440/10 = 144°

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