Year 8 Angles Worksheet — Level 2 — Practice Set 3 — 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 3 — Answers
State the angle rule you use.
1.Two angles on a straight line are 147° and x°. Find x.
Answer: x = 33
- Angles on a straight line add to 180°
- x = 180 − 147 = 33
2.Two angles on a straight line are 141° and x°. Find x.
Answer: x = 39
- Angles on a straight line add to 180°
- x = 180 − 141 = 39
3.Two angles of a triangle are 31° and 112°. Find the third angle.
Answer: 37°
- Angles in a triangle add to 180°
- 180 − 31 − 112 = 37
4.Two angles on a straight line are 83° and x°. Find x.
Answer: x = 97
- Angles on a straight line add to 180°
- x = 180 − 83 = 97
5.Two angles of a triangle are 40° and 53°. Find the third angle.
Answer: 87°
- Angles in a triangle add to 180°
- 180 − 40 − 53 = 87
6.Two angles on a straight line are 57° and x°. Find x.
Answer: x = 123
- Angles on a straight line add to 180°
- x = 180 − 57 = 123
7.Two angles on a straight line are 137° and x°. Find x.
Answer: x = 43
- Angles on a straight line add to 180°
- x = 180 − 137 = 43
8.Two angles on a straight line are 37° and x°. Find x.
Answer: x = 143
- Angles on a straight line add to 180°
- x = 180 − 37 = 143
9.Two angles on a straight line are 153° and x°. Find x.
Answer: x = 27
- Angles on a straight line add to 180°
- x = 180 − 153 = 27
10.Two angles on a straight line are 52° and x°. Find x.
Answer: x = 128
- Angles on a straight line add to 180°
- x = 180 − 52 = 128
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