7th Grade Angles Worksheet — Level 3 — Practice Set 2 — Answers
Answer sheet with worked solutions for the 7th Grade angles worksheet.
Success TutoringWorksheetsAnswer sheet7th Grade · Mathematics · Angles7th Grade Angles Worksheet — Level 3 — Practice Set 2 — Answers
State the angle rule you use.
1.Two angles of a triangle are 120° and 81°. Find the third angle.
Answer: -21°
- Angles in a triangle add to 180°
- 180 − 120 − 81 = -21
2.Three angles meet at a point: 67°, 109° and x°. Find x.
Answer: x = 184
- Angles at a point add to 360°
- x = 360 − 67 − 109 = 184
3.Two angles on a straight line are 113° and x°. Find x.
Answer: x = 67
- Angles on a straight line add to 180°
- x = 180 − 113 = 67
4.An isosceles triangle has an apex angle of 70°. Find each base angle.
Answer: 55°
- Base angles are equal: (180 − 70) ÷ 2
- = 110 ÷ 2 = 55
5.Three angles meet at a point: 49°, 68° and x°. Find x.
Answer: x = 243
- Angles at a point add to 360°
- x = 360 − 49 − 68 = 243
6.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
7.Three angles meet at a point: 135°, 46° and x°. Find x.
Answer: x = 179
- Angles at a point add to 360°
- x = 360 − 135 − 46 = 179
8.Two angles of a triangle are 23° and 104°. Find the third angle.
Answer: 53°
- Angles in a triangle add to 180°
- 180 − 23 − 104 = 53
9.An isosceles triangle has an apex angle of 76°. Find each base angle.
Answer: 52°
- Base angles are equal: (180 − 76) ÷ 2
- = 104 ÷ 2 = 52
10.Three angles meet at a point: 40°, 50° and x°. Find x.
Answer: x = 270
- Angles at a point add to 360°
- x = 360 − 40 − 50 = 270
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