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 on a straight line are 38° and x°. Find x.
Answer: x = 142
- Angles on a straight line add to 180°
- x = 180 − 38 = 142
2.An isosceles triangle has an apex angle of 61°. Find each base angle.
Answer: 59.5°
- Base angles are equal: (180 − 61) ÷ 2
- = 119 ÷ 2 = 59.5
3.Three angles meet at a point: 65°, 106° and x°. Find x.
Answer: x = 189
- Angles at a point add to 360°
- x = 360 − 65 − 106 = 189
4.Two angles of a triangle are 51° and 110°. Find the third angle.
Answer: 19°
- Angles in a triangle add to 180°
- 180 − 51 − 110 = 19
5.Two angles on a straight line are 142° and x°. Find x.
Answer: x = 38
- Angles on a straight line add to 180°
- x = 180 − 142 = 38
6.An isosceles triangle has an apex angle of 55°. Find each base angle.
Answer: 62.5°
- Base angles are equal: (180 − 55) ÷ 2
- = 125 ÷ 2 = 62.5
7.An isosceles triangle has an apex angle of 48°. Find each base angle.
Answer: 66°
- Base angles are equal: (180 − 48) ÷ 2
- = 132 ÷ 2 = 66
8.Two angles of a triangle are 39° and 30°. Find the third angle.
Answer: 111°
- Angles in a triangle add to 180°
- 180 − 39 − 30 = 111
9.Three angles meet at a point: 133°, 108° and x°. Find x.
Answer: x = 119
- Angles at a point add to 360°
- x = 360 − 133 − 108 = 119
10.An isosceles triangle has an apex angle of 40°. Find each base angle.
Answer: 70°
- Base angles are equal: (180 − 40) ÷ 2
- = 140 ÷ 2 = 70
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