Question

The diameter of a semicircle is 8 millimetres. What is the semicircle's radius?

Answer 1

The radius is 4.

Explanation:

Concepts:

• Diameter is usually defined as a straight line passing through the center of a circle or sphere and meeting the circumference or circle at each end.
• Radius is usually defined as a straight line extending from the center of a circle or sphere to the circumference of surface. (Half of diameter).

To figure this out:

R = 1/2 d

R = 1/2 8

R = 4