Parallel Lines Cut by a Transversal — Answer Key
A. Identify the Angles
- Corresponding angles → Equal
- Alternate interior angles → Equal
- Alternate exterior angles → Equal
- Co-interior angles → Add up to 180°
B. Find the Missing Angle
- 65°
- 115°
- 108°
- 128°
C. Solve for x
3x + 10 = 5x − 30
x = 20
4x + 8 = 6x − 22
x = 15
(3x + 15) + (2x + 25) = 180
x = 28
7x − 5 = 4x + 40
x = 15
D. Find the Angle
- Given 55°
- Corresponding = 55°
- Alternate interior = 55°
- Co-interior = 125°
- Given 120°
- Corresponding = 120°
- Alternate interior = 120°
- Co-interior = 60°
- Given 83°
- Corresponding = 83°
- Alternate interior = 83°
- Co-interior = 97°
E. True or False
- True
- True
- False
- True
- True
F. Challenge
- 4 angles measure 68°.
5x + 10 = 85
x = 15
(4x + 20) + (2x + 40) = 180
6x + 60 = 180
x = 20
Angles:
- 4(20) + 20 = 100°
- 2(20) + 40 = 80°