Question

Two cars are traveling in the same direction. The first car is going 40 mph and the second car is going 55 mph. The first car left 3 hours before the second car. What is the equation you need to use to find o it how many hours it will take for the second car to catch up to the first car?

Answer 1

same direction
distance=rate times time
d=rt

time that the first car had was x, at 40mph
d=40x

the 2nd car had x-3 hours, at 55mph
d=55(x-3)

when will the distances be the same?

40x=55(x-3)
divide both sides by 5
8x=11(x-3)
distribute
8x=11x-33
minus 8x both sides
0=3x-33
add 33 both sides
33=3x
diide both sides by 3
11=x
answer is after 11 hours (440 miles)