Eva maintained an average speed of v1 miles per hour for the first t1 hours of her road trip. For the next t2 hours of the trip, she drove at an average speed of v2. Eva drove a total of D miles in T hours. Which of the following systems of equations could be used to find how many miles Eva drove in the first t1 hours of the trip?
Q. Eva maintained an average speed of v1 miles per hour for the first t1 hours of her road trip. For the next t2 hours of the trip, she drove at an average speed of v2. Eva drove a total of D miles in T hours. Which of the following systems of equations could be used to find how many miles Eva drove in the first t1 hours of the trip?
Denote Average Speeds and Times: Let's denote the average speed for the first part of the trip as v1 (in miles per hour), the time for the first part as t1 (in hours), the average speed for the second part as v2, and the time for the second part as t2. The total distance is given as D and the total time as T. We can set up two equations: one for the distance covered in each part of the trip, and one for the total time of the trip.
Equation for Distance Covered: The distance Eva drove in the first part of the trip can be represented as v1×t1, and the distance in the second part as v2×t2. The total distance is the sum of these two distances, so we have the equation v1×t1+v2×t2=D.
Equation for Total Time: The total time of the trip is the sum of the time spent on each part, so we have the equation t1+t2=T.
Solving the System of Equations: Now we have a system of two equations with two variables (t1 and t2) that can be solved to find the distance Eva drove in the first part of the trip. The system of equations is:1) v1×t1+v2×t2=D2) t1+t2=T
More problems from Solve one-step and two-step linear equations: word problems