Question

If an interior angle of a regular polygon measures 140*, how many sides does it have?

Please involve a explanation so i can learn from it.
Here is the equation (n-2) x 180 / n

Answer 1

9 sides.

Explanation:

N is the # of sides.

140 = ((n-2) x 180) / n

Multiply both sides by n

140 n = (n-2) x 180

Distribute the right side

140 n = 180 n - 360

Subtract 140 n and add 360 to both sides.

40 n = 360

n = 9