All sides have the same length and angles have the same measure. A closed plane figure whose sides are segments that intersect only at their endpoints. Polygons: Regular Polygon: Convex: Concave: All sides have the same length and angles have the same measure. REGULAR TRIANGLE REGULAR QUADRILATERAL REGULAR PENTAGON REGULAR HEXAGON A polygon is convex if a segment joining any two interior points lies completely within the polygon A polygon that is not convex

and tell whether it is convex or concave. If not, explain why. Directions: Tell whether the figure is a polygon. If it is a polygon, classify it and tell whether it is convex or concave. If not, explain why. 1. 2. 3. Polygons # of Sides

A polygon with four sides Quadrilaterals: Some quadrilaterals have special names based on whether they have parallel or congruent sides and whether they have right angles. Name: Sides: Angles: A polygon with four sides TRAPEZOID PARALLELOGRAM RHOMBUS RECTANGLE SQUARE Exactly one pair of parallel sides Both pair of opposite sides are parallel Four congruent sides Four congruent sides Four right angles Four right angles

A segment that joins two vertices that are not adjacent Diagonal of a polygon: To find the sum of the interior angles of a polygon, you can cut up the polygon into ____________ using ______________. The sum of the interior angles of a triangle is: 1. Find the measures of the interior angles on each of the regular polygons. 2. Find the value of x. A segment that joins two vertices that are not adjacent TRIANGLES DIAGONALS Multiply by the number of triangles Divide by the number of angles to find each angle measure