Question 899744
Let speed of first vehicle be x
speed of second vehicle = (x+10)

Time traveled by first vehicle = 4 hours
Time traveled by second vehicle =3hours

D=rt

Distance traveled by first vehicle = 4x
distance traveled by second vehicle = 3(x+10)

They are 10 miles apart

4x-3(x+10)=10

4x-3x-30=10

x=30+10
x=40 

speed of first vehicle be 40 mph
speed of second vehicle = (x+10)
= 50 mph