Warm Up 01.09.12Week 2

Re 1 Give two names for the polygon:

dodecagon

concave

Section 6.1 Day 2

I will identify, name and describe polygons.

Ex 1

Equilateral Polygon

All sides must be congruent.

Ex 2

Equiangular Polygon

All angles must be congruent.

Ex 3

Regular Polygon

Must be equilateral and equiangular.

Diagonal of a polygon

A segment that joins two non-consecutive vertices.

Ex 4

consecutive

•

Quadrilateral Angles

Ex 5

Quadrilateral Angles

180º 180º

360º

Ex 5

Interior Angles of a Quadrilateral TheoremThe sum of the measures of the interior angles of a

quadrilateral equals 360º.

Theorem 6.1

1

23

4

m ∠ 1 + m ∠ 2 + m ∠ 3 + m ∠ 4 = 360º.

Ex 6

70 + 80 + 2x + x = 360

150 + 3x = 360

3x = 210

x = 70

70º

80º

xº

2xºP

Q R

S

2xº = m ∠ P

2( 70 )º = m ∠ P

140º = m ∠ P

What is m ∠ P ?

Textbook page 326, 27 - 51 All except #40.Assignment:

Review A _________ of a polygon is a segment that joins two nonconsecutive vertices.

45º

120º

9xº

6xº

P

Q

R

S

Do 1: What is the value of x?