Cheat Sheet for Polygons

[knight247]

Hey,
I'm kinda well versed with the interior and exterior angle formulas for regular polygons i.e.
(1)Sum of interior angles=(n-2)180
(2)Measure of one interior angle=(n-2)180/n

(3)Sum of exterior angles in one direction is 360 and in the other direction is 360
(4)Measure of one exterior angle=360/n

I'm a little confused though about the formulas for irregular polygons
I know that Formula No.1 still applies. Formula 2 does not. I guess I need some clarification on the exterior angles of irregular polygons. Hoping to get some help on that. Detailed explanations would be appreciated. Thanks

[Brent@GMATPrepNow]

Hey,
I'm kinda well versed with the interior and exterior angle formulas for regular polygons i.e.
(1)Sum of interior angles=(n-2)180
(2)Measure of one interior angle=(n-2)180/n

(3)Sum of exterior angles in one direction is 360 and in the other direction is 360
(4)Measure of one exterior angle=360/n

I'm a little confused though about the formulas for irregular polygons
I know that Formula No.1 still applies. Formula 2 does not. I guess I need some clarification on the exterior angles of irregular polygons. Hoping to get some help on that. Detailed explanations would be appreciated. Thanks

I wouldn't worry about the formulas for exterior angles.

For irregular polygons (where the sides and angles are not all equal) with n sides, the sum of the interior angle is still 180(n-2) degrees.

Since the angles are not equal in an irregular polygon, there is no formula for each interior angle.

Cheers,
Brent