Question 6106
1)  6x+9
 -(-2x+4)
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 6x+9
+2x-4
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8x+5

 {{{ 2x^2y-5xy^2+2}}}
{{{-(-x^2y+2xy^2+2)}}}
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distribute the negative throughout the parentheses:
 {{{ 2x^2y-5xy^2+2}}}
{{{+(x^2y-2xy^2-2)}}}
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{{{3x^2y-7xy^2}}}