Question

(x²+4)-(4x²y-3xy²+4)+(-3x²y-7xy²-7)

Answer 1

this is your answer of this question.

Answer 2

$\bf \: ( {x}^{2} + 4) - (4 {x}^{2} y - 3x {y}^{2} + 4) \\ \bf \: + ( - 3 {x}^{2} y - 7x {y}^{2} - 7) \\ \\ = {x}^{2} + 4 - 4 {x}^{2} y + 3x {y}^{2} + 4 - 3 {x}^{2} y \\ - 7x {y}^{2} - 7 \\ \\ = {x}^{2} - 4 {x}^{2} y - 3 {x}^{2} y + 3 {xy}^{2} - 7x {y}^{2} \\ + 4 + 4 - 7 \\ \\ = {x}^{2} - 7 {x}^{2} y - 4x {y}^{2} + 8 - 7 \\ \\ = \bf \: {x}^{2} - 7 {x}^{2} y - 4x {y}^{2} + 1$

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