Orchard Hideout Circles terms and definitions circle Set

Orchard Hideout • Circles – terms and definitions • circle: Set of points that are equidistant from a given point, which is know as the center

Orchard Hideout • Circles – terms and definitions • radius: (Measure of) line segment whose endpoints are the center and a point on the circle. radius

Orchard Hideout • Circles – terms and definitions • diameter: (Measure of) line segment whose endpoints are on the circle and whose midpoint is at the center of the circle. diameter The diameter is also at the widest part of the circle.

Orchard Hideout • Circles – terms and definitions • circumference: Distance around the circle. circumference Latin meaning of circum is "around"

Orchard Hideout • Circles – terms and definitions When working with circles, we will often have to use… … so where does this mysterious number come from? What does it have to do with circles? Let's find out!

Orchard Hideout • Circles – equations In each of the following equations: r = measure of radius d = measure of diameter C = measure of circumference

Orchard Hideout • Circles – calculating values Use the given value to find the other values: 1. If r = 7 units, then… d = _____ C = _____

Orchard Hideout • Circles – calculating values Use the given value to find the other values: 2. If d = 10. 5 units, then… r = _____ C = _____

Orchard Hideout • Circles – calculating values Use the given value to find the other values: 3. If C = 86π units, then… r = _____ d = _____

Orchard Hideout • Circles – calculating values Use the given value to find the other values: 4. If C = 30. 72 units, then… r _____ d _____

Orchard Hideout • Circles – calculating values 5. A circular pool has an approximate circumference of 56. 5 feet. What are the diameter and radius of the pool? Round to the nearest hundredth.

Orchard Hideout • Circles – calculating values 6. Find the measure of the radius of a circle whose diameter has endpoints at (7, 2) and (3, 8).