what you want to do is cross multiply so you get 5(x+4)=7(3x+28) then you distrubute the 5 and then you distribute the 5 and the 7 to the number in the parentheses 5x+20=21x+196
subtract 5x on both sides to get 20=16x+196 then you subtract 196 on both sides to get -176=16x last what you want to do is divide 16 on both sides to get x=-11