7th Grade Angles Worksheet — Level 3 — Answers
Answer sheet with worked solutions for the 7th Grade angles worksheet.
Success TutoringWorksheetsAnswer sheet7th Grade · Mathematics · Angles7th Grade Angles Worksheet — Level 3 — Answers
State the angle rule you use.
1.Two angles of a triangle are 25° and 104°. Find the third angle.
Answer: 51°
- Angles in a triangle add to 180°
- 180 − 25 − 104 = 51
2.An isosceles triangle has an apex angle of 26°. Find each base angle.
Answer: 77°
- Base angles are equal: (180 − 26) ÷ 2
- = 154 ÷ 2 = 77
3.An isosceles triangle has an apex angle of 64°. Find each base angle.
Answer: 58°
- Base angles are equal: (180 − 64) ÷ 2
- = 116 ÷ 2 = 58
4.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
5.Two angles of a triangle are 95° and 83°. Find the third angle.
Answer: 2°
- Angles in a triangle add to 180°
- 180 − 95 − 83 = 2
6.Two angles on a straight line are 109° and x°. Find x.
Answer: x = 71
- Angles on a straight line add to 180°
- x = 180 − 109 = 71
7.An isosceles triangle has an apex angle of 51°. Find each base angle.
Answer: 64.5°
- Base angles are equal: (180 − 51) ÷ 2
- = 129 ÷ 2 = 64.5
8.Three angles meet at a point: 42°, 97° and x°. Find x.
Answer: x = 221
- Angles at a point add to 360°
- x = 360 − 42 − 97 = 221
9.Two angles on a straight line are 37° and x°. Find x.
Answer: x = 143
- Angles on a straight line add to 180°
- x = 180 − 37 = 143
10.An isosceles triangle has an apex angle of 73°. Find each base angle.
Answer: 53.5°
- Base angles are equal: (180 − 73) ÷ 2
- = 107 ÷ 2 = 53.5
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