Year 8 Angles Worksheet — Level 3 — Practice Set 2 — 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 2 — Answers
State the angle rule you use.
1.Two angles of a triangle are 95° and 44°. Find the third angle.
Answer: 41°
- Angles in a triangle add to 180°
- 180 − 95 − 44 = 41
2.Two angles on a straight line are 138° and x°. Find x.
Answer: x = 42
- Angles on a straight line add to 180°
- x = 180 − 138 = 42
3.Two angles on a straight line are 121° and x°. Find x.
Answer: x = 59
- Angles on a straight line add to 180°
- x = 180 − 121 = 59
4.An isosceles triangle has an apex angle of 45°. Find each base angle.
Answer: 67.5°
- Base angles are equal: (180 − 45) ÷ 2
- = 135 ÷ 2 = 67.5
5.Two angles on a straight line are 131° and x°. Find x.
Answer: x = 49
- Angles on a straight line add to 180°
- x = 180 − 131 = 49
6.An isosceles triangle has an apex angle of 72°. Find each base angle.
Answer: 54°
- Base angles are equal: (180 − 72) ÷ 2
- = 108 ÷ 2 = 54
7.An isosceles triangle has an apex angle of 33°. Find each base angle.
Answer: 73.5°
- Base angles are equal: (180 − 33) ÷ 2
- = 147 ÷ 2 = 73.5
8.An isosceles triangle has an apex angle of 32°. Find each base angle.
Answer: 74°
- Base angles are equal: (180 − 32) ÷ 2
- = 148 ÷ 2 = 74
9.Two angles of a triangle are 30° and 37°. Find the third angle.
Answer: 113°
- Angles in a triangle add to 180°
- 180 − 30 − 37 = 113
10.Two angles of a triangle are 63° and 86°. Find the third angle.
Answer: 31°
- Angles in a triangle add to 180°
- 180 − 63 − 86 = 31
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