Year 7 Angles Worksheet — Level 3 — Answers
Answer sheet with worked solutions for the Year 7 angles worksheet.
Success TutoringWorksheetsAnswer sheetYear 7 · Mathematics · AnglesYear 7 Angles Worksheet — Level 3 — Answers
State the angle rule you use.
1.An isosceles triangle has an apex angle of 20°. Find each base angle.
Answer: 80°
- Base angles are equal: (180 − 20) ÷ 2
- = 160 ÷ 2 = 80
2.Two angles on a straight line are 92° and x°. Find x.
Answer: x = 88
- Angles on a straight line add to 180°
- x = 180 − 92 = 88
3.Three angles meet at a point: 151°, 43° and x°. Find x.
Answer: x = 166
- Angles at a point add to 360°
- x = 360 − 151 − 43 = 166
4.Two angles on a straight line are 58° and x°. Find x.
Answer: x = 122
- Angles on a straight line add to 180°
- x = 180 − 58 = 122
5.An isosceles triangle has an apex angle of 21°. Find each base angle.
Answer: 79.5°
- Base angles are equal: (180 − 21) ÷ 2
- = 159 ÷ 2 = 79.5
6.An isosceles triangle has an apex angle of 63°. Find each base angle.
Answer: 58.5°
- Base angles are equal: (180 − 63) ÷ 2
- = 117 ÷ 2 = 58.5
7.Two angles on a straight line are 105° and x°. Find x.
Answer: x = 75
- Angles on a straight line add to 180°
- x = 180 − 105 = 75
8.Three angles meet at a point: 144°, 116° and x°. Find x.
Answer: x = 100
- Angles at a point add to 360°
- x = 360 − 144 − 116 = 100
9.Three angles meet at a point: 122°, 108° and x°. Find x.
Answer: x = 130
- Angles at a point add to 360°
- x = 360 − 122 − 108 = 130
10.Two angles on a straight line are 70° and x°. Find x.
Answer: x = 110
- Angles on a straight line add to 180°
- x = 180 − 70 = 110
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