Polygon

Triangle

Quadrilateral

Pentagon

Hexagon

Heptagon

Sides

3

4

5

6

7

Interior Angle Sum

180

360

540

720

900

Use the chart and predict the sum of the measures of the interior angles for an nonagon.

a.

1080

c.

1440

b.

1260

d.

1630

All you have to do is add 180 for every side so if its a triangle with 3 sides then it would be 180 interior angle side measurements the adding another 180 to 180 you get 360 and that's a square. so the answer is 1260. Good luck with your Work! - Jeff