Central Angles and Supplementary Angles

The video tutorial explains how to find a central angle when given two diameters and an arc degree. It begins by establishing the equivalence of the degree measurement of the arc to the angle. The tutorial then discusses how angles lying along the same line segment are supplementary. Finally, it demonstrates solving for angle BOA by subtracting the known angle from 180°, resulting in BOA being 120°.

What is the first step in finding a central angle when given two diameters and an arc degree?

• Find the area of the circle.

• Calculate the circumference of the circle.

• Measure the radius of the circle.

• Recall the equivalence of the arc degree and the central angle.

If an arc measures 60°, what is the measure of the corresponding central angle?

• 90°

• 60°

• 120°

• 30°

What is the relationship between an arc degree and its central angle?

• The arc degree is equal to the central angle.

• The arc degree is half of the central angle.

• The arc degree is unrelated to the central angle.

• The arc degree is double the central angle.

If an arc measures 45°, what is the measure of the corresponding central angle?

• 45°

• 135°

• 90°

• 180°

What is the measure of a central angle if the arc degree is 90°?

• 180°

• 90°

• 45°

• 135°

What does it mean when two angles lie along the same line segment?

• They are supplementary.

• They are complementary.

• They are equal.

• They are congruent.

How do you find the measure of angle BOA if it is supplementary to a 60° angle?

• Add 60° to 90°.

• Divide 180° by 60°.

• Subtract 60° from 180°.

• Multiply 60° by 2.

What is the measure of angle BOA if it is supplementary to a 60° angle?

• 60°

• 150°

• 90°

• 120°

Which of the following is true about supplementary angles?

• They are always equal.

• Their sum is 180°.

• They are always less than 90°.

• Their sum is 90°.

If angle A and angle B are supplementary and angle A is 70°, what is angle B?

• 110°

• 180°

• 90°

• 70°