The number of sides of a regular polygon whose interior angle is 140

9

Step-by-step explanation:

The sum of the interior angle and the exterior angle = 180°

Thus the exterior angle of the polygon = 180° - 140° = 40°

The sum of the exterior angles of a polygon = 360°, thus

number of sides = 360° ÷ 40° = 9

step-by-step explanation:

it's equivalent, so we can say that its equal.

let's call the denominator x and the numerador is 18 less then denominator, x - 18.

multiply

2.x = 5.(x - 18)

2x = 5x - 90

90 = 5x - 2x

90 = 3x

x = 90/3

x = 30

so: