Year 8 Angles Worksheet — Level 3 — 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 3 — Practice Set 3 — Answers
State the angle rule you use.
1.Three angles meet at a point: 79°, 72° and x°. Find x.
Answer: x = 209
- Angles at a point add to 360°
- x = 360 − 79 − 72 = 209
2.Two angles on a straight line are 154° and x°. Find x.
Answer: x = 26
- Angles on a straight line add to 180°
- x = 180 − 154 = 26
3.Two angles of a triangle are 105° and 110°. Find the third angle.
Answer: -35°
- Angles in a triangle add to 180°
- 180 − 105 − 110 = -35
4.Three angles meet at a point: 98°, 51° and x°. Find x.
Answer: x = 211
- Angles at a point add to 360°
- x = 360 − 98 − 51 = 211
5.Two angles on a straight line are 79° and x°. Find x.
Answer: x = 101
- Angles on a straight line add to 180°
- x = 180 − 79 = 101
6.Two angles of a triangle are 75° and 51°. Find the third angle.
Answer: 54°
- Angles in a triangle add to 180°
- 180 − 75 − 51 = 54
7.An isosceles triangle has an apex angle of 58°. Find each base angle.
Answer: 61°
- Base angles are equal: (180 − 58) ÷ 2
- = 122 ÷ 2 = 61
8.Three angles meet at a point: 139°, 154° and x°. Find x.
Answer: x = 67
- Angles at a point add to 360°
- x = 360 − 139 − 154 = 67
9.Three angles meet at a point: 71°, 72° and x°. Find x.
Answer: x = 217
- Angles at a point add to 360°
- x = 360 − 71 − 72 = 217
10.Two angles on a straight line are 157° and x°. Find x.
Answer: x = 23
- Angles on a straight line add to 180°
- x = 180 − 157 = 23
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