Keller boat travels 24mph. find the rate of the river if she can travel 6 mi upstream. in the same amount of time she can go 10 mi downstream.

Given that Kellen can travel upstream in the same amount of time she travels downstream, the rate of river will be found as follow:
time=(distance)/(speed)
time taken to travel upstream is:
(24+x)/10
Time taken to travel downstream is:
(24-x)/6
given that the time taken to travel upstream and downstream is the same then:
(24+x)/10=(24-x)/6
6(24+x)=10(24-x)
144+6x=240-10x
6x+10x=240-144
16x=96
x=96/16
x=6 mph

Value for line ac: (3x+6)+(2x+14)= 5x+20