i would say to do the discount first by $12.00 because the coupon will always be a fixed number and that means that the discount varies depending on the price of the sofa. so say that the sofa is $100, if you use the discount first(which is 40% off and not $12.00) that lowers it to $60 then you use the coupon that takes off $5.00 you would only pay $55.00 for the sofa, but if you use the coupon first that will bring it down to $95, then do the 40% discount that will total to be $57. sry if im wrong, confused you, or answered too late.
