Year 6 Angles Worksheet — Level 3 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 6 angles worksheet.
Success TutoringWorksheetsAnswer sheetYear 6 · Mathematics · AnglesYear 6 Angles Worksheet — Level 3 — Practice Set 4 — Answers
State the angle rule you use.
1.An isosceles triangle has an apex angle of 32°. Find each base angle.
Answer: 74°
- Base angles are equal: (180 − 32) ÷ 2
- = 148 ÷ 2 = 74
2.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
3.Two angles on a straight line are 139° and x°. Find x.
Answer: x = 41
- Angles on a straight line add to 180°
- x = 180 − 139 = 41
4.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
5.Two angles on a straight line are 129° and x°. Find x.
Answer: x = 51
- Angles on a straight line add to 180°
- x = 180 − 129 = 51
6.An isosceles triangle has an apex angle of 35°. Find each base angle.
Answer: 72.5°
- Base angles are equal: (180 − 35) ÷ 2
- = 145 ÷ 2 = 72.5
7.Two angles of a triangle are 67° and 104°. Find the third angle.
Answer: 9°
- Angles in a triangle add to 180°
- 180 − 67 − 104 = 9
8.Two angles of a triangle are 21° and 23°. Find the third angle.
Answer: 136°
- Angles in a triangle add to 180°
- 180 − 21 − 23 = 136
9.Two angles of a triangle are 37° and 83°. Find the third angle.
Answer: 60°
- Angles in a triangle add to 180°
- 180 − 37 − 83 = 60
10.Two angles on a straight line are 104° and x°. Find x.
Answer: x = 76
- Angles on a straight line add to 180°
- x = 180 − 104 = 76
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