7th Grade Angles Worksheet — Level 3 — Practice Set 3 — 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 3 — Answers
State the angle rule you use.
1.Two angles on a straight line are 129° and x°. Find x.
Answer: x = 51
- Angles on a straight line add to 180°
- x = 180 − 129 = 51
2.An isosceles triangle has an apex angle of 21°. Find each base angle.
Answer: 79.5°
- Base angles are equal: (180 − 21) ÷ 2
- = 159 ÷ 2 = 79.5
3.Two angles on a straight line are 96° and x°. Find x.
Answer: x = 84
- Angles on a straight line add to 180°
- x = 180 − 96 = 84
4.Three angles meet at a point: 136°, 137° and x°. Find x.
Answer: x = 87
- Angles at a point add to 360°
- x = 360 − 136 − 137 = 87
5.Two angles of a triangle are 119° and 24°. Find the third angle.
Answer: 37°
- Angles in a triangle add to 180°
- 180 − 119 − 24 = 37
6.Two angles on a straight line are 90° and x°. Find x.
Answer: x = 90
- Angles on a straight line add to 180°
- x = 180 − 90 = 90
7.Two angles of a triangle are 109° and 50°. Find the third angle.
Answer: 21°
- Angles in a triangle add to 180°
- 180 − 109 − 50 = 21
8.Two angles of a triangle are 40° and 29°. Find the third angle.
Answer: 111°
- Angles in a triangle add to 180°
- 180 − 40 − 29 = 111
9.An isosceles triangle has an apex angle of 71°. Find each base angle.
Answer: 54.5°
- Base angles are equal: (180 − 71) ÷ 2
- = 109 ÷ 2 = 54.5
10.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
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