Year 9 Angles Worksheet — Level 3 — Practice Set 3 — Answers
Answer sheet with worked solutions for the Year 9 angles worksheet.
Success TutoringWorksheetsAnswer sheetYear 9 · Mathematics · AnglesYear 9 Angles Worksheet — Level 3 — Practice Set 3 — Answers
State the angle rule you use.
1.An isosceles triangle has an apex angle of 52°. Find each base angle.
Answer: 64°
- Base angles are equal: (180 − 52) ÷ 2
- = 128 ÷ 2 = 64
2.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
3.An isosceles triangle has an apex angle of 30°. Find each base angle.
Answer: 75°
- Base angles are equal: (180 − 30) ÷ 2
- = 150 ÷ 2 = 75
4.Three angles meet at a point: 47°, 88° and x°. Find x.
Answer: x = 225
- Angles at a point add to 360°
- x = 360 − 47 − 88 = 225
5.Three angles meet at a point: 62°, 81° and x°. Find x.
Answer: x = 217
- Angles at a point add to 360°
- x = 360 − 62 − 81 = 217
6.Two angles of a triangle are 93° and 44°. Find the third angle.
Answer: 43°
- Angles in a triangle add to 180°
- 180 − 93 − 44 = 43
7.Three angles meet at a point: 143°, 117° and x°. Find x.
Answer: x = 100
- Angles at a point add to 360°
- x = 360 − 143 − 117 = 100
8.Three angles meet at a point: 89°, 76° and x°. Find x.
Answer: x = 195
- Angles at a point add to 360°
- x = 360 − 89 − 76 = 195
9.Two angles of a triangle are 22° and 101°. Find the third angle.
Answer: 57°
- Angles in a triangle add to 180°
- 180 − 22 − 101 = 57
10.Two angles of a triangle are 118° and 65°. Find the third angle.
Answer: -3°
- Angles in a triangle add to 180°
- 180 − 118 − 65 = -3
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