A circle has an area of 49pi square units. What is the length of the circle's diameter?
The area of a circle is found by using the formula A=PiR^2 so a circle with an area of 49pi, 49 must be the radius squared (R^2)
The sqrt(49)=7 so the radius should be 7, the diameter is twice the length of the radius, or 2*7=14
14 units is the length of the diameter.
The area of the circle= pi*r^2
==> pi*r^2= 49*pi
==> r^2 = 49
==> r= 7
The diameter = 2 * radius = 1*7 = 14 units