Download Honors Geometry

Honors Geometry
1.4 Measure and Classify Angles
Objectives:
Name: ________________________________________
Date: _________________________ Block: ________
To name, measure, and classify angles
To answer, “How do you identify whether an angle is acute, right, obtuse, or straight?”
Key Vocabulary
Angle
Sides
Vertex
How to name: 1)
2)
3)
EXAMPLE 1
Name the three angles in the diagram
ERROR PREVENTION:
Measuring Angles
The tool used to approximate the measure of an angle is a ___________________________________ .
Measure <WXZ above.
Classifying Angles
EXAMPLE 2
Use the diagram to find the measure of the indicated angle. Then classify the angle
a. <KHL
b. <GHK
c. <GHJ
d. <GHL
Angle Addition Postulate
We write:
EXAMPLE 3
Given that m<LKN = 145, find the m<LKM and m<MKN.
Try these: 1.) Given that <KLM is a straight angle, find the m<KLN and m<NLM.
2.) <JRT is a straight angle intersected by ray RM. If m<JRM = x2 - 8x and m<MRT = 5x +
170, find the measure of <JRM and m<JRT.
Congruent Angles:
Angle Bisector -
To label a diagram with and angle bisector we use ____________________.
EXAMPLE 4
Draw an angle so that YW bisect <XYZ and the m<XYW = 18. With out using your
protractor to measure, what is the m<XYZ? Explain.
Draw and solve. Ray FQ is the angle bisector of <AFB. If m<AFQ = 12x + 32 and m<AFB =
20x + 70. Find the measure of all the angles.
Challenge!