5th Grade Angles Worksheet — Level 3 — Answers
Answer sheet with worked solutions for the 5th Grade angles worksheet.
Success TutoringWorksheetsAnswer sheet5th Grade · Mathematics · Angles5th Grade Angles Worksheet — Level 3 — Answers
State the angle rule you use.
1.An isosceles triangle has an apex angle of 40°. Find each base angle.
Answer: 70°
- Base angles are equal: (180 − 40) ÷ 2
- = 140 ÷ 2 = 70
2.Three angles meet at a point: 56°, 160° and x°. Find x.
Answer: x = 144
- Angles at a point add to 360°
- x = 360 − 56 − 160 = 144
3.An isosceles triangle has an apex angle of 44°. Find each base angle.
Answer: 68°
- Base angles are equal: (180 − 44) ÷ 2
- = 136 ÷ 2 = 68
4.Three angles meet at a point: 76°, 66° and x°. Find x.
Answer: x = 218
- Angles at a point add to 360°
- x = 360 − 76 − 66 = 218
5.Two angles on a straight line are 99° and x°. Find x.
Answer: x = 81
- Angles on a straight line add to 180°
- x = 180 − 99 = 81
6.Two angles on a straight line are 151° and x°. Find x.
Answer: x = 29
- Angles on a straight line add to 180°
- x = 180 − 151 = 29
7.Three angles meet at a point: 114°, 75° and x°. Find x.
Answer: x = 171
- Angles at a point add to 360°
- x = 360 − 114 − 75 = 171
8.Two angles of a triangle are 54° and 37°. Find the third angle.
Answer: 89°
- Angles in a triangle add to 180°
- 180 − 54 − 37 = 89
9.An isosceles triangle has an apex angle of 31°. Find each base angle.
Answer: 74.5°
- Base angles are equal: (180 − 31) ÷ 2
- = 149 ÷ 2 = 74.5
10.An isosceles triangle has an apex angle of 35°. Find each base angle.
Answer: 72.5°
- Base angles are equal: (180 − 35) ÷ 2
- = 145 ÷ 2 = 72.5
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