11) -104 = 8x
12) 14b=-56
13) -6 = b/18
14) 10n = 40

The discount is 8.70 . you dont tell us the percent of tax added so there is no way to find out, unless i'm not seeing anything. without tax its 37.70

Well if you’ve already proven it, all i can give you is tips. in a paragraph proof just remember to use words like therefore, because, and since to bridge the gap between a statement and it’s reason in a paragraph proof.