document.write( "Question 81770: How do I subtract and solve 2x – 3x2 + 5x3 from 5x3 + 4x – x2? \n" ); document.write( "
Algebra.Com's Answer #58593 by bucky(2189)\"\" \"About 
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Write down the \"from\" expression first and arrange its terms in descending powers of x
\n" ); document.write( "(x-cubed term first, x-squared term next, and x-term last). When you do you get:
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\n" ); document.write( "\"5x%5E3+-+x%5E2+%2B+4x\"
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\n" ); document.write( "Do the same thing to the \"take away\" term, and write it under the \"from\" expression
\n" ); document.write( "to get:
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\n" ); document.write( "\"5x%5E3+-+x%5E2+%2B+4x\"
\n" ); document.write( "\"5x%5E3+-+3x%5E2+%2B2x\"
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\n" ); document.write( "Next, change the signs of each term in the bottom row:
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\n" ); document.write( "\"5x%5E3+-+x%5E2+%2B+4x\"
\n" ); document.write( "\"-5x%5E3+%2B+3x%5E2+-2x\"
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\n" ); document.write( "On your paper, you can draw a line under the bottom expression, just as you would for
\n" ); document.write( "an ordinary subtraction problem involving numbers.
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\n" ); document.write( "Now all you have to do is add the like terms in the vertical columns. Seems odd that you
\n" ); document.write( "add, but by changing the signs of the terms in the bottom expression, you have converted
\n" ); document.write( "the problem from a subtraction problem to an addition problem.
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\n" ); document.write( "In the first vertical column you add \"5x%5E3+-+5x%5E3\" and note that they cancel out.
\n" ); document.write( "If you want, you can write a zero at the bottom of this column, or you can just leave it
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\n" ); document.write( ".
\n" ); document.write( "In the next vertical column you add \"-x%5E2+%2B+3x%5E2\" and the result is \"2x%5E2\".
\n" ); document.write( "You can write this term at the bottom of this vertical column.
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\n" ); document.write( "Finally, in the last column you add \"4x+-+2x\" and you get \"2x\". Write this at
\n" ); document.write( "bottom of the third vertical problem.
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\n" ); document.write( "Putting your answers together you should see the following terms in the bottom row:
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\n" ); document.write( "\"0+%2B+2x%5E2+%2B+2x\" and you just drop the zero to make the answer \"2x%5E2+%2B+2x\"
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\n" ); document.write( "With more practice you will be able to work problems such as these without writing
\n" ); document.write( "things in columns, but first you need to practice the pattern of subtraction and arranging
\n" ); document.write( "things in columns is a good way to start.
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\n" ); document.write( "Hope this helps. \n" ); document.write( "
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