Year 9 Angles Worksheet — Level 3 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 9 angles worksheet.
Success TutoringWorksheetsAnswer sheetYear 9 · Mathematics · AnglesYear 9 Angles Worksheet — Level 3 — Practice Set 4 — Answers
State the angle rule you use.
1.Three angles meet at a point: 152°, 112° and x°. Find x.
Answer: x = 96
- Angles at a point add to 360°
- x = 360 − 152 − 112 = 96
2.Three angles meet at a point: 45°, 146° and x°. Find x.
Answer: x = 169
- Angles at a point add to 360°
- x = 360 − 45 − 146 = 169
3.Two angles on a straight line are 108° and x°. Find x.
Answer: x = 72
- Angles on a straight line add to 180°
- x = 180 − 108 = 72
4.Two angles of a triangle are 117° and 102°. Find the third angle.
Answer: -39°
- Angles in a triangle add to 180°
- 180 − 117 − 102 = -39
5.Two angles of a triangle are 63° and 85°. Find the third angle.
Answer: 32°
- Angles in a triangle add to 180°
- 180 − 63 − 85 = 32
6.Two angles of a triangle are 55° and 21°. Find the third angle.
Answer: 104°
- Angles in a triangle add to 180°
- 180 − 55 − 21 = 104
7.Two angles on a straight line are 27° and x°. Find x.
Answer: x = 153
- Angles on a straight line add to 180°
- x = 180 − 27 = 153
8.Two angles of a triangle are 83° and 76°. Find the third angle.
Answer: 21°
- Angles in a triangle add to 180°
- 180 − 83 − 76 = 21
9.Three angles meet at a point: 131°, 113° and x°. Find x.
Answer: x = 116
- Angles at a point add to 360°
- x = 360 − 131 − 113 = 116
10.Two angles of a triangle are 47° and 41°. Find the third angle.
Answer: 92°
- Angles in a triangle add to 180°
- 180 − 47 − 41 = 92
Marking tips
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