SOLUTION: Solve the application problem Log2 (x) = 3-log2 (x-2)

 =  -  ----->  =  ----->  =  ----->

 = .

Factor it:

(x-4)*(x+2) = 0.

The roots are x = 4 and x = -2.

Negative x doesn't work due to logarithm . . . 

x = 4 works well.

Answer. x = 4.