| A | B |
|---|
| polygon | a plane figure that is formed by 3 or more sides |
| polygon | each side intersects exactly 2 other sides, one at each end-point |
| polygon | no 2 sides with a common endpoint are collinear |
| convex | if no line that contains a side of the polygon contains a point in the interior of the polygon. |
| nonconvex/concave | a polgon that is not convex |
| quadrilateral | 4 sided figure |
| hexagon | 6 sides |
| heptagon | 7 sides |
| nonagon | 9 sides |
| dodecagon | 12 sides |
| n-gon | any number of sides |
| to find the measures of the interior angles | (n-2)(180) |
| to find the measure of each interior angle | n-2(180)/2 |
| parallelogram | a quad. whose oppisite sides are parallel |
| quad=parall. | if both pairs of opposite sides are congruent. |
| quad=parall. | if both pairs of opposite angles are congruent |
| quad=parall | if an angle is supplementary to both consecutive angles |
| quad=parall. | if diagonals of a quad. bisect each other |
| sum of exterior angles | 360* |
| Rhombus | 4 congruent sides |
| rectangle | 4 right angles |
| square | four congruent sides adn right angles. |
| parall=rhombus | if its diagonals are perpendicular |
| parall=rhombus | each diagonal bisects a pair of opposite angles |
| parall=rectangle | diagonals are congruent |
| trapezoid is isosceles | each pair of base angles are congruent. |
| trapezoid is isosceles | its diagonals are congruent |
| quad=kite | diagonals are perpendicular |
| quad=kite | exactly one pair of opposite angles are congruent. |
