Polygon Names and Equations - Integrated 2 Math/Geometry

triangle

Three-sided polygon

quadrilateral

four-sided polygon

pentagon

five-sided polygon

hexagon

six-sided polygon

heptagon

seven-sided polygon

octagon

eight-sided polygon

nonagon

nine-sided polygon

decagon

ten-sided polygon

hendecagon

eleven-sided polygon

dodecagon

twelve-sided polygon

180(n-2)

equation for sum of interior angles in any polygon

(n = number of sides)

180(n-2)/n

equation for one interior angle in a regular polygon

(n = number of sides)

360

sum of exterior angles in any given polygon

360/n

measure of a singular exterior angle in any given polygon