Measuring Segments and Angles Notes for Section 1-4 Measuring Segments and Angles

We can think of the segment as part of a ___________ line. To measure a segment, we can use a ruler and measure the distance between the two ____________. OR We can think of the segment as part of a ___________ line. A B C D E F G H I - 4 - 3 - 2 - 1 1 2 3 4

| | = | | = Look at segment AE How can we determine the length of segment AE? The coordinate of A is _______ The coordinate of E is _______ | | = | | = A B C D E F G H I - 4 - 3 - 2 - 1 1 2 3 4

Two segments with the same ____, denoted __ Congruent Segments Two segments with the same ____, denoted __ Can you determine some congruent segments from the number line below? A B C D E F G H I - 4 - 3 - 2 - 1 1 2 3 4

Practice 1-4 # 4 - 7

An important postulate……. If three points A, B, and C are _______ and B is between A and C, then ________________.

Practice 1-4 # 1 – 3, 9 - 11

A midpoint _____ the segment. A point that divides a segment into two _________ segments. A midpoint _____ the segment.

Z is the midpoint of segment XY, and XY = 27. Find XZ. Let’s look at the following example. Z is the midpoint of segment XY, and XY = 27. Find XZ.

Practice 1-4 # 21 - 22

Angle __________________________ Formed by two _____ with the same endpoint, denoted ___ 1 B C There are four ways to name this angle. The endpoint is called the _____ of the angle. __________________________

One way to express the measure of an angle is in _________. 65° B We would write this as…… ______________

Angle Measuring Activity

An angle with measurement between ____ and ____ degrees. Acute Angle An angle with measurement between ____ and ____ degrees.

An angle with measurement of _____ degrees. Right Angle An angle with measurement of _____ degrees.

An angle with measurement between ____ and ___ degrees. Obtuse Angle An angle with measurement between ____ and ___ degrees.

An angle with measurement of ____ degrees. Straight Angle An angle with measurement of ____ degrees.

An important postulate…… If point B is in the ________ of AOC, then _________________________ A B O C

Angles with the same ________. Congruent Angles Angles with the same ________. For example… If ____________, Then ____________

Practice 1-4 # 8, 12 - 20