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.Three angles meet at a point: 123°, 85° and x°. Find x.
Answer: x = 152
- Angles at a point add to 360°
- x = 360 − 123 − 85 = 152
2.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
3.Three angles meet at a point: 80°, 56° and x°. Find x.
Answer: x = 224
- Angles at a point add to 360°
- x = 360 − 80 − 56 = 224
4.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
5.An isosceles triangle has an apex angle of 42°. Find each base angle.
Answer: 69°
- Base angles are equal: (180 − 42) ÷ 2
- = 138 ÷ 2 = 69
6.An isosceles triangle has an apex angle of 22°. Find each base angle.
Answer: 79°
- Base angles are equal: (180 − 22) ÷ 2
- = 158 ÷ 2 = 79
7.Two angles of a triangle are 39° and 62°. Find the third angle.
Answer: 79°
- Angles in a triangle add to 180°
- 180 − 39 − 62 = 79
8.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
9.An isosceles triangle has an apex angle of 75°. Find each base angle.
Answer: 52.5°
- Base angles are equal: (180 − 75) ÷ 2
- = 105 ÷ 2 = 52.5
10.Two angles of a triangle are 38° and 111°. Find the third angle.
Answer: 31°
- Angles in a triangle add to 180°
- 180 − 38 − 111 = 31
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