Year 7 Angles Worksheet — Level 3 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 7 angles worksheet.
Success TutoringWorksheetsAnswer sheetYear 7 · Mathematics · AnglesYear 7 Angles Worksheet — Level 3 — Practice Set 4 — Answers
State the angle rule you use.
1.An isosceles triangle has an apex angle of 56°. Find each base angle.
Answer: 62°
- Base angles are equal: (180 − 56) ÷ 2
- = 124 ÷ 2 = 62
2.Two angles on a straight line are 55° and x°. Find x.
Answer: x = 125
- Angles on a straight line add to 180°
- x = 180 − 55 = 125
3.An isosceles triangle has an apex angle of 78°. Find each base angle.
Answer: 51°
- Base angles are equal: (180 − 78) ÷ 2
- = 102 ÷ 2 = 51
4.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
5.Two angles of a triangle are 88° and 54°. Find the third angle.
Answer: 38°
- Angles in a triangle add to 180°
- 180 − 88 − 54 = 38
6.Two angles on a straight line are 27° and x°. Find x.
Answer: x = 153
- Angles on a straight line add to 180°
- x = 180 − 27 = 153
7.Two angles on a straight line are 140° and x°. Find x.
Answer: x = 40
- Angles on a straight line add to 180°
- x = 180 − 140 = 40
8.An isosceles triangle has an apex angle of 60°. Find each base angle.
Answer: 60°
- Base angles are equal: (180 − 60) ÷ 2
- = 120 ÷ 2 = 60
9.Three angles meet at a point: 111°, 77° and x°. Find x.
Answer: x = 172
- Angles at a point add to 360°
- x = 360 − 111 − 77 = 172
10.Two angles on a straight line are 150° and x°. Find x.
Answer: x = 30
- Angles on a straight line add to 180°
- x = 180 − 150 = 30
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