Year 9 Angles Worksheet — Level 2 — Practice Set 3 — Answers
Answer sheet with worked solutions for the Year 9 angles worksheet.
Success TutoringWorksheetsAnswer sheetYear 9 · Mathematics · AnglesYear 9 Angles Worksheet — Level 2 — Practice Set 3 — Answers
State the angle rule you use.
1.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
2.Two angles of a triangle are 72° and 115°. Find the third angle.
Answer: -7°
- Angles in a triangle add to 180°
- 180 − 72 − 115 = -7
3.Two angles on a straight line are 31° and x°. Find x.
Answer: x = 149
- Angles on a straight line add to 180°
- x = 180 − 31 = 149
4.Two angles of a triangle are 98° and 119°. Find the third angle.
Answer: -37°
- Angles in a triangle add to 180°
- 180 − 98 − 119 = -37
5.Two angles on a straight line are 50° and x°. Find x.
Answer: x = 130
- Angles on a straight line add to 180°
- x = 180 − 50 = 130
6.Two angles of a triangle are 93° and 77°. Find the third angle.
Answer: 10°
- Angles in a triangle add to 180°
- 180 − 93 − 77 = 10
7.Two angles of a triangle are 107° and 88°. Find the third angle.
Answer: -15°
- Angles in a triangle add to 180°
- 180 − 107 − 88 = -15
8.Two angles of a triangle are 76° and 79°. Find the third angle.
Answer: 25°
- Angles in a triangle add to 180°
- 180 − 76 − 79 = 25
9.Two angles on a straight line are 127° and x°. Find x.
Answer: x = 53
- Angles on a straight line add to 180°
- x = 180 − 127 = 53
10.Two angles of a triangle are 54° and 118°. Find the third angle.
Answer: 8°
- Angles in a triangle add to 180°
- 180 − 54 − 118 = 8
Marking tips
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