Recall your d = rt.
so hmm is about the same as the other one... so say the boat has a speed rate of "b", well, going downstream the boat goes say " b + 2 ", because the current is adding to it, and going upstream is " b - 2 " because the current is eroding from it.
So if the whole trip took 14 hours, say it took "t" hours going upstream, then going downstream it took the slack or " 14 - t ".
Also notice, the trip forth and back is the same 45 miles.
so hmm is about the same as the other one... so say the boat has a speed rate of "b", well, going downstream the boat goes say " b + 2 ", because the current is adding to it, and going upstream is " b - 2 " because the current is eroding from it.
So if the whole trip took 14 hours, say it took "t" hours going upstream, then going downstream it took the slack or " 14 - t ".
Also notice, the trip forth and back is the same 45 miles.