Year 8 Angles Worksheet — Level 3 — Practice Set 4 — 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 4 — Answers
State the angle rule you use.
1.An isosceles triangle has an apex angle of 64°. Find each base angle.
Answer: 58°
- Base angles are equal: (180 − 64) ÷ 2
- = 116 ÷ 2 = 58
2.Two angles of a triangle are 97° and 114°. Find the third angle.
Answer: -31°
- Angles in a triangle add to 180°
- 180 − 97 − 114 = -31
3.Two angles on a straight line are 24° and x°. Find x.
Answer: x = 156
- Angles on a straight line add to 180°
- x = 180 − 24 = 156
4.An isosceles triangle has an apex angle of 77°. Find each base angle.
Answer: 51.5°
- Base angles are equal: (180 − 77) ÷ 2
- = 103 ÷ 2 = 51.5
5.Two angles of a triangle are 117° and 107°. Find the third angle.
Answer: -44°
- Angles in a triangle add to 180°
- 180 − 117 − 107 = -44
6.An isosceles triangle has an apex angle of 65°. Find each base angle.
Answer: 57.5°
- Base angles are equal: (180 − 65) ÷ 2
- = 115 ÷ 2 = 57.5
7.Three angles meet at a point: 40°, 120° and x°. Find x.
Answer: x = 200
- Angles at a point add to 360°
- x = 360 − 40 − 120 = 200
8.An isosceles triangle has an apex angle of 25°. Find each base angle.
Answer: 77.5°
- Base angles are equal: (180 − 25) ÷ 2
- = 155 ÷ 2 = 77.5
9.Two angles on a straight line are 152° and x°. Find x.
Answer: x = 28
- Angles on a straight line add to 180°
- x = 180 − 152 = 28
10.Two angles on a straight line are 68° and x°. Find x.
Answer: x = 112
- Angles on a straight line add to 180°
- x = 180 − 68 = 112
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