solve the following proportion for x 3/8=x/13 round to the nearest tenth

I read that as:

x^3 / 8 = x/13
13x^3 = 8x
13x^3 - 8x = 0
x(13x^2 - 8) = 0
x = 0 or
x^2 = 8/13 ----> x = ± √(8/13) = .... , surely you have a calculator