(x +3)^(3/2) - 11 = 53
(x +3)^(3/2) = 53 + 11
(x +3)^(3/2) = 64
Raise each side of the equation to power (2/3)
(x +3)^(3/2)^(2/3) = 64^(2/3)
(x +3)^(3/2 * 2/3) = 64^(2/3)
(x +3)^(1) = (∛64)^(2). Cube root of 64 = 4.
(x + 3) = 4^2
x +3 = 16
x = 16 - 3
x = 13
option c.
Hope this helps.