Here's the problem:
A bicycler and a car driver started driving towards each other from towns A and B.
After they had drove for an hour the car driver sped up by 20 km/h. If the car wouldn't have changed its speed, the bicycler and car driver would've met one hour later. The distance between two towns is 480km. Find the speed of bicycler and car driver.


Here's what I have done:
let x be the speed of the bicycler
y be the speed of the car
t be the time it would've taken them to meet if the car didn't speed up.

x + y + x(t-2) + (t-2)(y+20)=480

tx + ty =480

^^Simultaneous equations
Which can't be solved, I think :\..

Any tips?

Actually, I believe you did an excellent job of setting up the problem. If you work it out and substitute 480 where you see tx + ty and then again later 480/t where you see (x + y) your should end up with a nice factorable quadratic giving two solutions one positive and one negative. We know which one to take.

You wanted a hint rather than the answer so I'll stop here.

Bob C