Answer:
6
Step-by-step explanation:
h = 8
Surface area = 66π
2πr(r +h) = 66π
2πr(r + 8) = 66π
[tex]r(r + 8) =\dfrac{66\pi }{2\pi }[/tex]
r² + 8r = 33
r² + 8r - 33 = 0
r² + 11r - 3r - 33 = 0
r(r + 11) - 3(r + 11) = 0
(r +11 ) (r - 3) = 0
r - 3 = 0 {Ignore r = -11 as radius will not have negative value}
r = 3
Diameter = 3*2 = 6 units
