I'm assuming you mean (a-b)^2 : (a+b)^2
a^2 + b^2 cancel out leaving
-2ab versus +2ab
Therefore (a+b)^2 is +4ab greater.
34.95 x 18%= 6.29
34.95-6.29= 28.66
$28.66 is the sale price
Hello Leyla! Could you provide details about the plumbing services? I’d be happy to help you in the comments.