8th Grade Angles Worksheet — Level 3 — Practice Set 4 — Answers
Answer sheet with worked solutions for the 8th Grade angles worksheet.
Success TutoringWorksheetsAnswer sheet8th Grade · Mathematics · Angles8th Grade Angles Worksheet — Level 3 — Practice Set 4 — Answers
State the angle rule you use.
1.Three angles meet at a point: 150°, 68° and x°. Find x.
Answer: x = 142
- Angles at a point add to 360°
- x = 360 − 150 − 68 = 142
2.An isosceles triangle has an apex angle of 65°. Find each base angle.
Answer: 57.5°
- Base angles are equal: (180 − 65) ÷ 2
- = 115 ÷ 2 = 57.5
3.An isosceles triangle has an apex angle of 41°. Find each base angle.
Answer: 69.5°
- Base angles are equal: (180 − 41) ÷ 2
- = 139 ÷ 2 = 69.5
4.Two angles of a triangle are 89° and 110°. Find the third angle.
Answer: -19°
- Angles in a triangle add to 180°
- 180 − 89 − 110 = -19
5.Two angles on a straight line are 40° and x°. Find x.
Answer: x = 140
- Angles on a straight line add to 180°
- x = 180 − 40 = 140
6.Three angles meet at a point: 114°, 70° and x°. Find x.
Answer: x = 176
- Angles at a point add to 360°
- x = 360 − 114 − 70 = 176
7.Three angles meet at a point: 137°, 100° and x°. Find x.
Answer: x = 123
- Angles at a point add to 360°
- x = 360 − 137 − 100 = 123
8.Two angles on a straight line are 21° and x°. Find x.
Answer: x = 159
- Angles on a straight line add to 180°
- x = 180 − 21 = 159
9.Three angles meet at a point: 156°, 79° and x°. Find x.
Answer: x = 125
- Angles at a point add to 360°
- x = 360 − 156 − 79 = 125
10.Two angles on a straight line are 111° and x°. Find x.
Answer: x = 69
- Angles on a straight line add to 180°
- x = 180 − 111 = 69
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