[polly]

   Hi everyone..
I am working on applying the steady rate approximation for a reaction and this is i think more of a maths problem but I really cant understand how to simplify the following rate expression. I have simplified it to the following

d[HCOOH]/dt  = -K₁[HCOOH] + K_-1[H⁺]K₁[HCOOH] / K_-1[H⁺] + K₂[Br₂]

but am not sure if I can cancel K_-1[H⁺] from the top and bottom...and do the -K₁[HCOOH] and K₁[HCOOH] cancel too? ...mmm...

thanks...