The polynomial is simplified by combining like terms. Like terms are identified more easily if the variables in each term are written in the same order. We usually like to use alphabetical order. Two of the like terms have opposite coefficients, so they cancel. The result is ...
(3 1/2 -2 1/2)xy² +(-2 4/5 +2 4/5)x²y
= xy² . . . . simplified expression
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For x = 1, y = -2, the value of the expression is ...
