Distance Speed and time with 2 variables?

this one is sort of long...

Maurice drove 400 km from Edmonton to Battleford in one hour less time than it took Martin to drive the same route from Battleford to Edmonton. If Maurice drove 20km/h faster than Martin, at what speed did each of them drive? Show a complete algebraic solution.

So far, all I have is...

Martin

Distance - 400 km

Speed - s

Time - t

Maurice

Distance - 400 km

Speed - s + 20

Time - t - 1

Not getting anywhere with this, though.

Thanks in advance.