Year 8 Angles Worksheet — Level 2 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 8 angles worksheet.
Success TutoringWorksheetsAnswer sheetYear 8 · Mathematics · AnglesYear 8 Angles Worksheet — Level 2 — Practice Set 4 — Answers
State the angle rule you use.
1.Two angles of a triangle are 112° and 61°. Find the third angle.
Answer: 7°
- Angles in a triangle add to 180°
- 180 − 112 − 61 = 7
2.Two angles of a triangle are 118° and 92°. Find the third angle.
Answer: -30°
- Angles in a triangle add to 180°
- 180 − 118 − 92 = -30
3.Two angles on a straight line are 134° and x°. Find x.
Answer: x = 46
- Angles on a straight line add to 180°
- x = 180 − 134 = 46
4.Two angles of a triangle are 27° and 55°. Find the third angle.
Answer: 98°
- Angles in a triangle add to 180°
- 180 − 27 − 55 = 98
5.Two angles on a straight line are 125° and x°. Find x.
Answer: x = 55
- Angles on a straight line add to 180°
- x = 180 − 125 = 55
6.Two angles on a straight line are 100° and x°. Find x.
Answer: x = 80
- Angles on a straight line add to 180°
- x = 180 − 100 = 80
7.Two angles on a straight line are 92° and x°. Find x.
Answer: x = 88
- Angles on a straight line add to 180°
- x = 180 − 92 = 88
8.Two angles of a triangle are 73° and 51°. Find the third angle.
Answer: 56°
- Angles in a triangle add to 180°
- 180 − 73 − 51 = 56
9.Two angles on a straight line are 158° and x°. Find x.
Answer: x = 22
- Angles on a straight line add to 180°
- x = 180 − 158 = 22
10.Two angles on a straight line are 139° and x°. Find x.
Answer: x = 41
- Angles on a straight line add to 180°
- x = 180 − 139 = 41
Marking tips
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