Problema Solution
two cars leave at the same time and travel in the same direction. The faster car travels two times as fast as the slow car. After 2.5 hours they are 85 miles apart. What is the speed of each car?
Answer provided by our tutors
let
v1 = the speed of the faster car
v2 = the speed of the slow car
t = 2.5 h the time of the travel
the faster car travels two times as fast as the slow car
v1 = 2v2
after 2.5 hours they are 85 miles apart
the distance traveled by the fast car - the distance traveled by the slow car = 85 miles
since speed = distance/time => distance = speed*time
v1*t - v2*t = 85
t(v1 - v2) = 85
2.5(v1 - v2) = 85 divide both sides by 2.5
v1 - v2 = 34
by solving the system of equations
v1 = 2v2
v1 - v2 = 34
we find
v1 = 68 mph
v2 = 34 mph
click here to see the step by step solution of the system of equations
the speed of the faster car is 68 mph.
the speed of the slow car is 34 mph.