pre calcalus
posted by sara .
(x+4)^2/3=9

(x+4)^(2/3) = 9
To do this, we raise both side by 3/2, so that the exponent 2/3 of the term on the left side will be cancelled:
(x + 4)^(2/3 * 3/2) = 9^(3/2)
(x + 4)^(1) = 3^3
x + 4 = 27
x = 27  4
x = 23
To check, substitute the x value to the original equation:
(23 + 4)^(2/3) = 9
27^(2/3) = 9
3^2 = 9
9 = 9
Thus x is indeed equal to 23.
Hope this helps~ :3