Math 8: Triangles and Angle Measures
Section #2: Supplementary Angles
Corresponds with 7th grade Module 6, Lesson 1- 4
Notes # 34
___
Straight Angle: an angle whose measure is exactly __________, and forms a straight line.
Supplementary Angles: Two or more angles that form a ____________________ line, meaning that
the sum of the angles is____________.
60°
30°
Example # 1
In a complete sentence, describe the angle relationships in the diagram. Write an equation for the
angle relationship shown in the figure and solve for 𝑥.
134°
x
Example # 2
Set up and solve an equation to find the value of 𝑥. Find the measurement of ∠𝐴𝑂𝐵 and of ∠𝐵𝑂𝐶.
Example #3: The measures of two
supplementary angles are in the ratio
of 2: 3. Find the two angles.
Example #4: Find the missing angle
measures.
38°
43°
m°
n°
You Try
1.) Find the measure of x
34°
2.) Find the measure of each angle.
10x°
x
3.) Find the measure of x
2x°
4.) Find the missing angle measures
.
x
25°
x + 10
40°
y
Name:
Section #3: Supplementary Angles
Corresponds with 7th grade Module 6, Lesson 1
Math 8
HW# 28
Name:
Supplementary Angles
1.) Find the measure of x and y using an
equation for both.
x°
y°
16°
2.) Write an equation to solve for x.
45°
58°
x°
3.) The measure of a supplement of an angle is 6° more than twice the measure of the angle. Find
the two angles.
4.) The ratio of the measurement of an angle to its supplement is 3: 5. Find the angle and its
supplement.