>>1487695>I cant fifure out whyBecause just like your typing you've made a stupid school boy error and you didn't bother to check.
Fix what I've noted and that will correct your x coeff and your constant term.
>>1487700>you needed to slow the fuck downI'd say he needs to write things in order too. His working is a mess. Constant from the x expansion, then the first constant, then the constant from the y. Expand then group then simplify.