5th Grade Angles Worksheet — Level 3 — Practice Set 4 — Answers
Answer sheet with worked solutions for the 5th Grade angles worksheet.
Success TutoringWorksheetsAnswer sheet5th Grade · Mathematics · Angles5th Grade Angles Worksheet — Level 3 — Practice Set 4 — Answers
State the angle rule you use.
1.An isosceles triangle has an apex angle of 74°. Find each base angle.
Answer: 53°
- Base angles are equal: (180 − 74) ÷ 2
- = 106 ÷ 2 = 53
2.Two angles of a triangle are 98° and 85°. Find the third angle.
Answer: -3°
- Angles in a triangle add to 180°
- 180 − 98 − 85 = -3
3.An isosceles triangle has an apex angle of 69°. Find each base angle.
Answer: 55.5°
- Base angles are equal: (180 − 69) ÷ 2
- = 111 ÷ 2 = 55.5
4.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
5.Two angles on a straight line are 55° and x°. Find x.
Answer: x = 125
- Angles on a straight line add to 180°
- x = 180 − 55 = 125
6.Two angles on a straight line are 120° and x°. Find x.
Answer: x = 60
- Angles on a straight line add to 180°
- x = 180 − 120 = 60
7.Two angles of a triangle are 120° and 47°. Find the third angle.
Answer: 13°
- Angles in a triangle add to 180°
- 180 − 120 − 47 = 13
8.An isosceles triangle has an apex angle of 50°. Find each base angle.
Answer: 65°
- Base angles are equal: (180 − 50) ÷ 2
- = 130 ÷ 2 = 65
9.An isosceles triangle has an apex angle of 39°. Find each base angle.
Answer: 70.5°
- Base angles are equal: (180 − 39) ÷ 2
- = 141 ÷ 2 = 70.5
10.Three angles meet at a point: 132°, 96° and x°. Find x.
Answer: x = 132
- Angles at a point add to 360°
- x = 360 − 132 − 96 = 132
Marking tips
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