Do Now (Reflection) Take a protractor from the front of the room.Take out your compass.Answer the following questions in your notebook:How did I feel about the first unit test? (Level of

difficulty, level of preparation)What (if anything) will I do differently to prepare

for the second unit test?What can Ms. Forsyth do to help me better in unit

2?

Intro to AnglesUnit 2

Today’s ObjectivesReflect on Unit 1Show the measurement of angles and segments

on figuresMeasure angles using a protractorExplain congruence of anglesUse problem solving skills

Overall Test Results

Period 1

Period 2

Period 4

Period 5

Period 6

AngleAn angle is formed

by two (noncollinear) rays that share a common endpoint.

The common endpoint of the two rays is the vertex of the angle.

The two rays are the sides of the angle.

Naming an angleBy three letters with the

vertex in the middleOr by just the vertex

letter ONLY IF it there is only one angle with that vertex.

Can also be named by a number or a variable.

PracticeName all the angles in this drawing

The measure of an angleThe smallest amount of rotation about the vertex

from one ray to the other, measured in degrees.Can be any value between 0o and 180o.

Reflex measure of an angleThe largest amount of rotation less than 360o.The measure of an angle and the reflex measure

of an angle always add up to 360o.

How to measure an angleWith a protractor!Step 1: Place the center mark of the protractor on

the vertex of the angle you want to measure.Step 2: Line up the 0-mark with one side of the

angle.Step 3: Read the measure on the protractor scale.Step 4: Be sure you read the scale that has the 0-

mark you are using!

To show the measure of an angle

Use an m before the angle symbol. For example, m CAB=30o.

Congruent anglesTwo angles are congruent if and only if they have

equal measure. Use identical markings to show that two angles in

a figure are congruent.Two types of markings for angles

Angle BisectorsA ray is an angle bisector if it contains the vertex

and divides the angle into two congruent angles.

Name the angle bisectorA

Clock handsFind the angle formed by the hands of a clock at

2:00

PracticeName this angle in 3 different ways.

PracticeDraw and label the angles TANm BIG = 35o.

Today’s ObjectivesReflect on Unit 1Show the measurement of angles and segments

on figuresMeasure angles using a protractorExplain congruence of anglesUse problem solving skills

HomeworkComplete your “1.2 Poolroom Math” worksheet by

tomorrow.

Group Exit Slip!1. What is the relationship between the measure of

an angle and the reflex measure of an angle?2. Using a protractor, draw a clock face with hands

to show 8:00. 3. Measure the angle formed by your clock hands in

#2 and use correct notation to write the measure of the angle.

4. Draw a figure that contains at least three angles and includes an angle bisector. Mark any congruent angles.