Answer: " 4x + 2xy - 7pq " .
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Step-by-step explanation:
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Given: " 4x - 7xy + 9xy - 7pq " ; Simplify the expression;
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Combine the "like terms:
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-7xy + 9xy = 2xy ;
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Now, rerewrite the expression, substituting the "-7xy + 9xy"; with " + 2xy" ;
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→ " 4x + 2xy - 7pq " .
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