SOLUTION: can you please assist me with solving problem...instructions... 7x^2 + 5x from 9x^2 - 3.

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Question 71691: can you please assist me with solving problem...instructions...
7x^2 + 5x from 9x^2 - 3.

Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
7x^2 + 5x from 9x^2 - 3
.
The word "from" indicates to me that you are being asked to subtract 7x%5E2+%2B+5x from
9x%5E2+-+3.
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The rule of subtraction is that you change all the signs of the terms in the "take away"
polynomial, and then add the result to the "take from" polynomial.
.
In this case the "take way" polynomial is 7x%5E2+%2B5x. Change the signs to get:
.
+-7x%5E2+-+5x.
.
Then add this to the "take from" polynomial which is 9x%5E2+-+3
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You can only add numbers to numbers and can only add together terms with like powers of x.
In this case we can add the -7x%5E2 and the %2B9x%5E2 terms to get (((+ 2x^2))).
That's one part of the answer.
.
Next we have -5x and we need to add it to the "take from" polynomial. There is no
corresponding term with just an x in the "take from" polynomial, so the -5x
simply adds into the answer set unchanged. So far our answer is 2x%5E2+-+5x.
We have a -3 in the "take from" polynomial but there is no corresponding plain-old
number in the "take away" polynomial to add it to. Therefore -3 appears in the answer set
unchanged.
.
So by combining all the terms in the answer we get an answer of 2x%5E2+-+5x+-+3.
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Hope this helps you to understand the problem and the subtraction process a little better.