Learn how to determine the measure of a semi circle

The video tutorial explains how to find the measure of arc CDA by determining if it is a minor or major arc. For minor arcs, the central angle is used, while for major arcs, the central angle is subtracted from 360 degrees. The tutorial highlights that if line AC is the diameter, the arc from C to A is a semicircle, measuring 180 degrees.

What is the first step in finding the measure of arc CDA?

• Find the radius of the circle

• Determine if the arc is minor or major

• Calculate the length of the arc

• Measure the diameter

How do you find the measure of a major arc?

• Add the central angle to 180 degrees

• Subtract the central angle from 360 degrees

• Double the central angle

• Divide the central angle by 2

What is the measure of a semicircle?

• 90 degrees

• 180 degrees

• 360 degrees

• 270 degrees

If line AC is the diameter, what type of arc is CDA?

• Quarter circle

• Semicircle

• Major arc

• Minor arc

What is the significance of line AC being the diameter in the context of arc CDA?

• It makes arc CDA a minor arc

• It makes arc CDA a major arc

• It makes arc CDA a semicircle

• It makes arc CDA a full circle