The area of a circle can be found using the formula A = πr^2. If the area of a circle is equal to the expression (81c^2 - 72c + 16)πft^2, what is the value of the radius?
r = (9c - 4)
r = (9c + 7)
r = (3c - 4)
r = (3c + 7)
To find the value of the radius, we need to compare the given expression (81c^2 - 72c + 16)πft^2 to the formula for the area of a circle A = πr^2.
From the given expression, we see that the coefficient of the r^2 term is 81, which means that r = 9.
Therefore, the value of the radius is r = (9c - 4).