Question

Stacy travels 3 times as fast as Mike. Traveling in opposite directions, they are 392 miles apart after 7 hours. Find their rates of travel.Step 1 of 2: Use the variables x and y to set up two equations to solve the given problem.

Answer 1

Let's use the variable x to represent Stacy's speed and the variable y to represent Mike's speed.

If Stacy is 3 times faster than Mike, we have the first equation:

$x=3y$

Then, their distance is 392 miles after 7 hours when traveling in opposite directions, so we have:

$7x+7y=392$

So the system of equations that represents this problem is:

$\begin{cases}x=3y \\ 7x+7y=392\end{cases}$