Question 764839
Speed of boat in still water = x
2hrs * (x + 12mph) = 6hrs * (x - 12)
            2x + 24 = 6x - 72
           2x - 6x = - 72 - 
               - 4x = - 96
                  x = 24
Speed of boat in still water = 24mph
Proof:
2x + 24 = 6x - 72
2(24) + 24 = 6(24) - 72
       72 = 72
Hope this helps.
:-)