Basic Constant Travel Rate Rule is RT=D to relate rate, time, distance.
Arrange all described data into tabular form and look for how to fill any empty spots and form equations. Use variables as much as you can or as much as you need.
SPEED TIME DISTANCE
TO SANTA FE r t 480
TO PHOENIX r+5 t-(25/60) 480
Simply equating the terms or expressions for the distance is not enough.
You can and will need this system,
which can be somewhat simplified into .
Solving that for r and t is must algebra or arithmetic steps. You will do two substitution steps.