Section 1-4 Measuring Angles and Segments

_______________________

What is the measure of segment DC?

What is the measure of segment DE?

What is the measure of segment BC?

Postulate 1-5

The distance between any two points is the absolute value of the difference of the corresponding numbers

AB | A – B |

Congruent

Two segments with the same length are congruent.

Segment BC DE is it the same as

BC = DE

Segment Addition Postulate

If three points A, B and C are collinear and b is between A and C, then AB + BC = AC

Angle

Is formed by two rays with the same endpoint

Types of Angles

Angles are measured in degrees

Protractor – measures angles

Acute Angle – degree measure between 0 and 90 degrees

Types of Angles

Right Angle - measures exactly 90 degrees

Obtuse Angle – measures between 90 and 180 degrees.

Straight Angle – measures exactly 180 degrees

Angle Addition Posulate

Ex:

Pg 30

#32

Homework pg 28-29

2-16evens #13, 28, 33-35