10.1 Naming Polygons

Vocabulary What You'll Learn Naming Polygons What You'll Learn You will learn to name polygons according to the number of _____ and ______. sides angles Vocabulary 1) regular polygon 2) convex 3) concave

A polygon is named by the number of its _____ or ______. sides angles Naming Polygons A polygon is a _____________ in a plane formed by segments, called sides. closed figure A polygon is named by the number of its _____ or ______. sides angles A triangle is a polygon with three sides. The prefix ___ means three. tri

Prefixes are also used to name other polygons. Prefix Number of Sides Naming Polygons Prefixes are also used to name other polygons. Prefix Number of Sides Name of Polygon tri- 3 triangle quadri- 4 quadrilateral penta- 5 pentagon hexa- 6 hexagon hepta- 7 heptagon octa- 8 octagon nona- 9 nonagon deca- 10 decagon

Terms Naming Polygons A vertex is the point of intersection of two sides. Consecutive vertices are the two endpoints of any side. U T S Q R P A segment whose endpoints are nonconsecutive vertices is a diagonal. Sides that share a vertex are called consecutive sides.

An equilateral polygon has all _____ congruent. sides Naming Polygons An equilateral polygon has all _____ congruent. sides An equiangular polygon has all ______ congruent. angles A regular polygon is both ___________ and ___________. equilateral equiangular equilateral but not equiangular equiangular but not equilateral regular, both equilateral and equiangular Investigation: As the number of sides of a series of regular polygons increases, what do you notice about the shape of the polygons?

A polygon can also be classified as convex or concave. Naming Polygons A polygon can also be classified as convex or concave. If all of the diagonals lie in the interior of the figure, then the polygon is ______. If any part of a diagonal lies outside of the figure, then the polygon is _______. concave convex

Naming Polygons End of Section 10.1