So, apparently you are having trouble solving the equation 165 = d^(3/2). What exactly is your difficulty? To remind, one solves equations by applying the same transformation to both sides with the goal of making one side to be the unknown variable. E.g., given 5 = 3 + x, we add -3 to both sides to get -3 + 5 = -3 + 3 + x = x.

Why do you use a question mark in this sentence?