Circles-Circumference Flashcards
Math
1
Q
What is a radius?
A
The distance from the center to any point on the circle
2
Q
What is a formula for radius?
A
R=d/2
3
Q
What is a diameter?
A
The distance across the circle through the center.
4
Q
What is the formula of an diameter?
A
d=2r
5
Q
What is circumference?
A
The distance around the circle
6
Q
What are the two formulas of circumference?
A
c=d(pi) or c=2r(pi)
7
Q
Using 3.14 for pi: The radius is 6m. Find the area of the circle.
A
A= (pi)r2
A= (3.14) (6 to the power of 2)
A= (3.14) (36)
A= 113.04
8
Q
Leave in terms of pi: the radius is 9m. Find the area of the circle.
A
A= (pi)r2
A= pi(9 to the power of 2)
A= pi(81)
A= 81(pi) m2
