What is the surface area of a right cone whose radius is 8 and with a length of 16?
By "length"....I'm assuming that you mean "height"
Surface area of bottom = pi^r^2 plus
Surface area of the side = pi * r * √ (r^2 + h^2)
So we have
pi * (8)^2 + pi * 8 * √ [ 8^2 + 16^2 ] ≈ 650.65 square units
