Answer: 10
Explanation:
Let x be the measure of each exterior angle ( in degrees) .
Then the measure of each interior angle ( in degrees) = 4x
We know that the sum of exterior angle and interior angle = 180 degrees.
i.e. x+4x= 180
i.e. 5x = 180
i.e. x= 36 [Divide both sides by 5]
i.e. The measure of each exterior angle= 36°
Also, Sum all exterior angles is 360° .
Number of sides in regular polygon = 360° ÷ (Measure of each exterior angle)
= 360° ÷ 36
=10
Therefore , the number of sides in this regular polygon= 10