The answer is: " -3x² + 6 " .
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Step-by-step explanation:
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(2x² + 3x - 4) + (8 - 3x) + (- 5x² + 2) =
2x² + 3x - 4 + 8 - 3x + 1(- 5x² + 2) ;
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Note: 1(-5x² + 2) = - 5x² + 2 ;
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2x² + 3x - 4 + 8 - 3x + 1(- 5x² + 2) =
2x² + 3x - 4 + 8 - 3x - 5x² + 2 = ?
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Combine the "like terms" ;
+2x² - 5x² = - 3x² ;
+3x -3x = 0
-4 + 8 + 2 = 6 ;
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So, we have: " - 3x² + 6 " .
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