04/18/23

Geometry

Section 6.1Polygons

Polygon

1. A plane figure formed by three or more segments called sides.

2. Each side intersects exactly two other sides, one at each endpoint

Sides: the segments that form the polygon.

Vertex: an endpoint of a side of the polygon

No Curves!

A closed figure.

Identifying Polygons

C D

one of its sides intersects

more than two other sides

A

B

E

some of its sides are notsegments (No curves allowed!)

two of the sides intersect

only one other side (Must be a closed figure)

NamesPolygons are named by the # of sides they have

34567891012n

TriangleQuadrilateralPentagonHexagonHeptagonOctagonNonagonDecagonDodecagonn-gon

Convex polygon:

.

If you extend any of the sides, the side will not cut through the polygon.

Concave polygon: If you extend a side, the side may cut through the polygon.

Equilateral polygon: All sides are

Equiangular polygon:all interior angles are .

Identifying Convex and Concave Polygons

6hexagon

convex

concave

heptagon7

Identify the polygon and state whether it is convex or concave

Regular polygons

A polygon is regular if it is both

__________and ___________

Diagonal: ____________________ ____________________.

equilateral equiangular.

A segment that joins two nonconsecutive vertices.

Quadrilateral

Convex

Not regular

Pentagon

Concave

Not regular Regular

Hexagon

Convex

8 200 360x 360

8 160x -200 -200

8 8x = 20

5(20)=

3(20)+10= 70

360

360

100

90 90 100 360m D

280 360m D

80m D

First, solve for x

4 4 2 2 360x x x x 12 360x

30x

2 2(30) 60m D x

• End

• Assignment:

Pg.325 #12-34 even, 37-45 odd

04/18/23

Geometry

Section 6.1Polygons

Polygon

Sides:

Vertex:

Identifying Polygons

NamesPolygons are named by the # of sides they have

34567891012n

Convex polygon:

Concave polygon:

Equilateral polygon:

Equiangular polygon:

Identifying Convex and Concave Polygons

Identify the polygon and state whether it is convex or concave

Regular polygons

A polygon is regular if it is both

__________and ___________

Diagonal: ____________________ ____________________.