Motion with Constant Acceleration help

[a.train12]

Homework Statement

Two cars drive on a straight highway. At time t = 0, car 1 passes mile marker 0 traveling due east with a speed of 18.0 m/s. At the same time, car 2 is 0.90 km east of mile marker 0 traveling at 30.0 m/s due west. Car 1 is speeding up with an acceleration of magnitude 0.40 m/s^2, and car 2 is slowing down with an acceleration of magnitude 0.80 m/s^2.

Homework Equations

I have used that data to create an X vs T equation
x1=(18.0 m/s)t+(0.2)t^2;\;x2=900 m -(30.0 m/s)t+(0.4)t^2

The Attempt at a Solution

I cannot show an attempt because i have searched in the book how to find where they meet and am unsuccessful. Can anyone tell me how to figure this out starting from the beginning? Thank You!

 

[CompuChip]

You seem to have been careful with the signs, and your equations look correct.

If you set x1 = x2, you will find the time instant at which they meet.