What is the sum of a six sided polygon?

There is a formula for the total of the interior angles. A triangle (3 sides) adds up to 180°. A quadrilateral adds up to 360°. A pentagon adds up to 540° and a hexagon adds up to 720°. Notice that for each additional side, the sum of the interior angles increases by 180°.

The general formula for an 'n' sided polygon is:

(n-2) * 180°

So (6-2) * 180°

= 4 * 180° = 720° (like I said before)