Question 526349
Let 
Miles = x
Day = d

Change dollar into cents
$20=20*100=2000cents
$22=22*100=2200cents

2000*d+x*14 = 2200*d+x10
2000d+14x=2200d+10x
14x-10x=2200-2000
4x=200
x=200/4
x=50
For 50 miles the cost of both rental car fees will be the same



Check
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Miles = 50
Day = 1

One Company will Charge for one day and 50 miles

1 day charges = $20
50 miles charges = 14*50=700cents=$7

Total Charges = 20+7=$27



Other Company will Charge for one day and 50 miles

1 day charges = $22
50 miles charges = 10*50=500cents=$5

Total Charges = 22+5=$27