Angles and their relations
Answers are for parents and teachers.
1
Name the type of each angle: 45°, 90°, 120°, 180°, 200°.
Acute, right, obtuse, straight, reflex.
2
m(∠ABC) = 28°. Find its complement and its supplement.
Complement 90° − 28° = 62°. Supplement 180° − 28° = 152°.
3
Two lines cross and one angle is 125°. Find the other three angles.
The opposite angle is 125°. The others are 180° − 125° = 55° each.
4
Angles x, 2x and 3x lie on a straight line. Find x and the angles.
x + 2x + 3x = 180, 6x = 180, x = 30. The angles are 30°, 60° and 90°.
5
In the figure, name the pair formed by angles 4 and 5, and the pair formed by angles 2 and 6.
4 and 5 are alternate angles. 2 and 6 are corresponding angles.