Year 9 Angles Worksheet — Level 3 — Practice Set 2 — 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 2 — Answers
State the angle rule you use.
1.An isosceles triangle has an apex angle of 49°. Find each base angle.
Answer: 65.5°
- Base angles are equal: (180 − 49) ÷ 2
- = 131 ÷ 2 = 65.5
2.An isosceles triangle has an apex angle of 48°. Find each base angle.
Answer: 66°
- Base angles are equal: (180 − 48) ÷ 2
- = 132 ÷ 2 = 66
3.An isosceles triangle has an apex angle of 33°. Find each base angle.
Answer: 73.5°
- Base angles are equal: (180 − 33) ÷ 2
- = 147 ÷ 2 = 73.5
4.Three angles meet at a point: 64°, 70° and x°. Find x.
Answer: x = 226
- Angles at a point add to 360°
- x = 360 − 64 − 70 = 226
5.Two angles on a straight line are 69° and x°. Find x.
Answer: x = 111
- Angles on a straight line add to 180°
- x = 180 − 69 = 111
6.Two angles of a triangle are 56° and 84°. Find the third angle.
Answer: 40°
- Angles in a triangle add to 180°
- 180 − 56 − 84 = 40
7.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
8.Three angles meet at a point: 98°, 92° and x°. Find x.
Answer: x = 170
- Angles at a point add to 360°
- x = 360 − 98 − 92 = 170
9.Two angles on a straight line are 156° and x°. Find x.
Answer: x = 24
- Angles on a straight line add to 180°
- x = 180 − 156 = 24
10.Three angles meet at a point: 94°, 126° and x°. Find x.
Answer: x = 140
- Angles at a point add to 360°
- x = 360 − 94 − 126 = 140
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