Year 5 Angles Worksheet — Level 3 — Answers
Answer sheet with worked solutions for the Year 5 angles worksheet.
Success TutoringWorksheetsAnswer sheetYear 5 · Mathematics · AnglesYear 5 Angles Worksheet — Level 3 — Answers
State the angle rule you use.
1.An isosceles triangle has an apex angle of 53°. Find each base angle.
Answer: 63.5°
- Base angles are equal: (180 − 53) ÷ 2
- = 127 ÷ 2 = 63.5
2.Three angles meet at a point: 85°, 144° and x°. Find x.
Answer: x = 131
- Angles at a point add to 360°
- x = 360 − 85 − 144 = 131
3.An isosceles triangle has an apex angle of 57°. Find each base angle.
Answer: 61.5°
- Base angles are equal: (180 − 57) ÷ 2
- = 123 ÷ 2 = 61.5
4.Three angles meet at a point: 129°, 57° and x°. Find x.
Answer: x = 174
- Angles at a point add to 360°
- x = 360 − 129 − 57 = 174
5.An isosceles triangle has an apex angle of 66°. Find each base angle.
Answer: 57°
- Base angles are equal: (180 − 66) ÷ 2
- = 114 ÷ 2 = 57
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.Three angles meet at a point: 47°, 79° and x°. Find x.
Answer: x = 234
- Angles at a point add to 360°
- x = 360 − 47 − 79 = 234
8.Two angles on a straight line are 94° and x°. Find x.
Answer: x = 86
- Angles on a straight line add to 180°
- x = 180 − 94 = 86
9.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
10.An isosceles triangle has an apex angle of 36°. Find each base angle.
Answer: 72°
- Base angles are equal: (180 − 36) ÷ 2
- = 144 ÷ 2 = 72
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