Year 5 Angles Worksheet — Level 3 — Practice Set 2 — 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 2 — Answers
State the angle rule you use.
1.Two angles of a triangle are 76° and 86°. Find the third angle.
Answer: 18°
- Angles in a triangle add to 180°
- 180 − 76 − 86 = 18
2.Three angles meet at a point: 84°, 105° and x°. Find x.
Answer: x = 171
- Angles at a point add to 360°
- x = 360 − 84 − 105 = 171
3.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
4.Three angles meet at a point: 67°, 103° and x°. Find x.
Answer: x = 190
- Angles at a point add to 360°
- x = 360 − 67 − 103 = 190
5.An isosceles triangle has an apex angle of 23°. Find each base angle.
Answer: 78.5°
- Base angles are equal: (180 − 23) ÷ 2
- = 157 ÷ 2 = 78.5
6.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
7.Two angles of a triangle are 109° and 107°. Find the third angle.
Answer: -36°
- Angles in a triangle add to 180°
- 180 − 109 − 107 = -36
8.Two angles of a triangle are 73° and 104°. Find the third angle.
Answer: 3°
- Angles in a triangle add to 180°
- 180 − 73 − 104 = 3
9.Two angles on a straight line are 130° and x°. Find x.
Answer: x = 50
- Angles on a straight line add to 180°
- x = 180 − 130 = 50
10.Two angles of a triangle are 39° and 113°. Find the third angle.
Answer: 28°
- Angles in a triangle add to 180°
- 180 − 39 − 113 = 28
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