Geometry: 1.4 Angle Measure NOTES

Objectives: The student will be able to

x Measure and classify angles x Identify and use congruent angles and the bisector of an angle

Vocabulary

Word Definition Example Ray

Opposite Rays

Angle

Sides

Vertex

Interior

Exterior

Geometry: 1.4 Angle Measure NOTES

Example 1: Angles and Their Pairs

a) Name all the angles that have B as a vertex.

b) Name the sides of <5

c) Write another name for <6

d) Which angle has point X as a vertex?

e) Which ray is a side of <3

f) Which of the following is another name for <3

Right Angle Acute Angle Obtuse Angle

Geometry: 1.4 Angle Measure NOTES

Example 2: Measure and Classify Angles

1) Classify each angle as right, acute or obtuse. Then use a protractor to measure the angle to the nearest degree.

a) <TYV b) <WYT c) <TYU

Word Definition Example Congruent Angles

Angle Bisector

Geometry: 1.4 Angle Measure NOTES

Example 3: Measure and Classify Angles

a) Wall stickers of standard shapes are often used to provide a stimulating environment for a young child’s room. A five-pointed star sticker is shown with vertices labeled. Find m<GBH and m<HCI if < 𝐺𝐵𝐻 ≅ < 𝐻𝐶𝐼 , m<GBH = 2x + 5, and m<HCI = 3x - 10.

b)