Year 9 Angles Worksheet — Level 3 — Answers
Answer sheet with worked solutions for the Year 9 angles worksheet.
Success TutoringWorksheetsAnswer sheetYear 9 · Mathematics · AnglesYear 9 Angles Worksheet — Level 3 — Answers
State the angle rule you use.
1.Two angles on a straight line are 137° and x°. Find x.
Answer: x = 43
- Angles on a straight line add to 180°
- x = 180 − 137 = 43
2.Two angles on a straight line are 43° and x°. Find x.
Answer: x = 137
- Angles on a straight line add to 180°
- x = 180 − 43 = 137
3.Three angles meet at a point: 64°, 48° and x°. Find x.
Answer: x = 248
- Angles at a point add to 360°
- x = 360 − 64 − 48 = 248
4.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
5.Two angles on a straight line are 98° and x°. Find x.
Answer: x = 82
- Angles on a straight line add to 180°
- x = 180 − 98 = 82
6.Two angles of a triangle are 33° and 101°. Find the third angle.
Answer: 46°
- Angles in a triangle add to 180°
- 180 − 33 − 101 = 46
7.Three angles meet at a point: 49°, 77° and x°. Find x.
Answer: x = 234
- Angles at a point add to 360°
- x = 360 − 49 − 77 = 234
8.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
9.An isosceles triangle has an apex angle of 39°. Find each base angle.
Answer: 70.5°
- Base angles are equal: (180 − 39) ÷ 2
- = 141 ÷ 2 = 70.5
10.Three angles meet at a point: 118°, 123° and x°. Find x.
Answer: x = 119
- Angles at a point add to 360°
- x = 360 − 118 − 123 = 119
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