Question 406664
car speed = x
other car speed = x+10

..
The combined speed = x+x+10= 2x+10

D= 500 miles
rate = 2x+10
time = 5

500/(2x+10)=5
cross multiply
500 = 5(2x+10)
500=10x+50
10x=450
/10
x=45 mph

other car = x+10 = 55 mph