8th Grade Angles Worksheet — Level 2 — Practice Set 2 — Answers
Answer sheet with worked solutions for the 8th Grade angles worksheet.
Success TutoringWorksheetsAnswer sheet8th Grade · Mathematics · Angles8th Grade Angles Worksheet — Level 2 — Practice Set 2 — Answers
State the angle rule you use.
1.Two angles on a straight line are 99° and x°. Find x.
Answer: x = 81
- Angles on a straight line add to 180°
- x = 180 − 99 = 81
2.Two angles of a triangle are 108° and 55°. Find the third angle.
Answer: 17°
- Angles in a triangle add to 180°
- 180 − 108 − 55 = 17
3.Two angles of a triangle are 111° and 88°. Find the third angle.
Answer: -19°
- Angles in a triangle add to 180°
- 180 − 111 − 88 = -19
4.Two angles on a straight line are 33° and x°. Find x.
Answer: x = 147
- Angles on a straight line add to 180°
- x = 180 − 33 = 147
5.Two angles of a triangle are 94° and 29°. Find the third angle.
Answer: 57°
- Angles in a triangle add to 180°
- 180 − 94 − 29 = 57
6.Two angles of a triangle are 39° and 65°. Find the third angle.
Answer: 76°
- Angles in a triangle add to 180°
- 180 − 39 − 65 = 76
7.Two angles on a straight line are 132° and x°. Find x.
Answer: x = 48
- Angles on a straight line add to 180°
- x = 180 − 132 = 48
8.Two angles on a straight line are 80° and x°. Find x.
Answer: x = 100
- Angles on a straight line add to 180°
- x = 180 − 80 = 100
9.Two angles on a straight line are 29° and x°. Find x.
Answer: x = 151
- Angles on a straight line add to 180°
- x = 180 − 29 = 151
10.Two angles of a triangle are 106° and 34°. Find the third angle.
Answer: 40°
- Angles in a triangle add to 180°
- 180 − 106 − 34 = 40
Marking tips
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