A man bicycles 5.4 mph faster than he can walk. He bicycles a distance of 32.4 miles and then hikes back along the same route. If the entire trip takes 12.6 hours, how fast does he walk?

Equation: let x= walk rate

$\displaystyle \frac{32.4}{x}+\frac{32.4}{x+5.4}=12.6$

I think I set this equation up wrong...