Year 8 Angles Worksheet — Level 3 — Answers
Answer sheet with worked solutions for the Year 8 angles worksheet.
Success TutoringWorksheetsAnswer sheetYear 8 · Mathematics · AnglesYear 8 Angles Worksheet — Level 3 — Answers
State the angle rule you use.
1.Two angles on a straight line are 51° and x°. Find x.
Answer: x = 129
- Angles on a straight line add to 180°
- x = 180 − 51 = 129
2.Three angles meet at a point: 101°, 142° and x°. Find x.
Answer: x = 117
- Angles at a point add to 360°
- x = 360 − 101 − 142 = 117
3.Three angles meet at a point: 46°, 111° and x°. Find x.
Answer: x = 203
- Angles at a point add to 360°
- x = 360 − 46 − 111 = 203
4.An isosceles triangle has an apex angle of 76°. Find each base angle.
Answer: 52°
- Base angles are equal: (180 − 76) ÷ 2
- = 104 ÷ 2 = 52
5.Two angles on a straight line are 55° and x°. Find x.
Answer: x = 125
- Angles on a straight line add to 180°
- x = 180 − 55 = 125
6.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
7.Two angles of a triangle are 41° and 110°. Find the third angle.
Answer: 29°
- Angles in a triangle add to 180°
- 180 − 41 − 110 = 29
8.Two angles on a straight line are 120° and x°. Find x.
Answer: x = 60
- Angles on a straight line add to 180°
- x = 180 − 120 = 60
9.Three angles meet at a point: 107°, 154° and x°. Find x.
Answer: x = 99
- Angles at a point add to 360°
- x = 360 − 107 − 154 = 99
10.Two angles of a triangle are 28° and 43°. Find the third angle.
Answer: 109°
- Angles in a triangle add to 180°
- 180 − 28 − 43 = 109
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