Originally Posted by

**Mirado** This does not require a system of equations, that's a little overkill.

So, when you are setting up linear equations, you should know that a general linear equation looks like this: y=mx+b, where m is the slope and b is the y-intercept. So, you need to find the slope here, which you find using the equation $\displaystyle m=(y_2 - y_1)/(x_2 - x_1)$

So, what points will you use for this little formula above?

The linear equation in 2 variables they are talking about is the above, as opposed to the x=4 or y=10 linear equations.

Once you find out the slope here, you can use the point-slope formula to find your equation $\displaystyle y - y_1 = m(x - x_1)$

Ok, so you have your equation. Now just plus in 3 for the variable you used for miles and simplify.

Let me know if that helped