Year 5 Angles Worksheet — Level 3 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 5 angles worksheet.
Success TutoringWorksheetsAnswer sheetYear 5 · Mathematics · AnglesYear 5 Angles Worksheet — Level 3 — Practice Set 4 — Answers
State the angle rule you use.
1.Three angles meet at a point: 160°, 63° and x°. Find x.
Answer: x = 137
- Angles at a point add to 360°
- x = 360 − 160 − 63 = 137
2.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
3.An isosceles triangle has an apex angle of 74°. Find each base angle.
Answer: 53°
- Base angles are equal: (180 − 74) ÷ 2
- = 106 ÷ 2 = 53
4.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
5.Two angles of a triangle are 69° and 89°. Find the third angle.
Answer: 22°
- Angles in a triangle add to 180°
- 180 − 69 − 89 = 22
6.Two angles of a triangle are 48° and 39°. Find the third angle.
Answer: 93°
- Angles in a triangle add to 180°
- 180 − 48 − 39 = 93
7.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
8.Three angles meet at a point: 138°, 126° and x°. Find x.
Answer: x = 96
- Angles at a point add to 360°
- x = 360 − 138 − 126 = 96
9.Two angles on a straight line are 145° and x°. Find x.
Answer: x = 35
- Angles on a straight line add to 180°
- x = 180 − 145 = 35
10.Two angles on a straight line are 123° and x°. Find x.
Answer: x = 57
- Angles on a straight line add to 180°
- x = 180 − 123 = 57
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