Question

How many sides does a polygon have if the sum of its interior angles is 1260

Answer 1

One angle is 360/n

We can use x as the angle and n as the number of sides.

nx=360

so lets do this,

(2n - 4 )*90 = 1260
2n - 4 = 1260 / 90
2n - 4 = 42 / 3
2n - 4 = 14
2n = 18
n = 9

x is equal to 360/9
x is equal to 40 degrees for each exterior angle
so the interior angle's measurement would be 140 degrees

So the polygon would have 9 sides, the answer is 9.

Answer 2

The easiest way to find out the number of sides a polygon has is to use the equation (n-2)*180, with n being the number of sides.
n-2*180=1260
n-2=7
n=9
This polygon has 9 sides.