Question 1050250
Let r be the rate of the boat in still water. Then:
60/(r+2.5)+2=60/(r-2.5)
60(r-2.5)+2(rē-6.25)=60(r+2.5)
60r-150+2rē-12.5=60r+150
2rē-312.5=0
4rē-625=0
(2r+25)(2r-25)=0
r=12.5, -12.5
The rate of the boat in still water is 12.5 km/h. ☺☺☺☺