Question 373959
<pre>
Subtract 3x²+5x-1 from 7x³-x²+4x+6

    7x³ - x² + 4x + 6
       -(3x² + 5x - 1)
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Remove the parentheses by changing all the signs:

    7x³ -  x² + 4x + 6
        - 3x² - 5x + 1
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Now add vertically term by term:

    7x³ -  x² + 4x + 6
        - 3x² - 5x + 1
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    7x³ - 4x² -  x + 7

Edwin</pre>