I'm extremely thick headed for some reason so help would be appreciated.

Ok so lets say I paid $22.69 for a pizza. The sale tax rate is 8%. Now I need to find the price of the pizza alone.

My question is, why can't I just subtract 8% from the 22.69 to get my answer? When I read the problem, that's the first solution my brain comes up with (to just subtract 8% off the price that already has 8% added to it.)