First of all, don't cry. Second of all, try to post a clearer picture because it was a bit tough to see. Third of all, here are the answers:
In row 9, S is wrong because it is 27x+24y, it should be 36x+24y In row 10, A is wrong because it is 4+20x, it should be 20x In row 11, G is wrong because it is 15ab, it should be 10a+5b In row 12, I is wrong because it is 15x+6y, it should be 15x+10y In row 13, O is wrong because it is 22a+6, it should be 28a In row 14, T is wrong because it is 14x, it should be 22x In row 15, K is wrong because it is 15x+y, it should be 15x+3y In row 16, T is wrong because it is 14n+84m, it should be 12m+14n
Also on another note, this might be intimidating but it is mostly adding/multiplication of variables. So if you don't know them, you might want to double check that you know how to handle variables in the future;)
To find the non-equivalent expression, compare the given expressions by simplifying them and checking their forms. Expressions that simplify to different values or forms will indicate which one is non-equivalent. Specific expressions are needed to provide exact answers.
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