document.write( "Question 1145014: Factor by grouping (sometimes called the ac-method).
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\n" ); document.write( "7x^2 + 12x - 4 \n" ); document.write( "
Algebra.Com's Answer #766203 by solver91311(24713)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "First you are looking for two factors of the form and so that , hence:\r
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\n" ); document.write( "\n" ); document.write( "So, as long as we confine ourselves to the integers for the values of p, q, r, and s, we can see right away that either and or vice versa. For q and s, we have more choices. Clearly, one of them is negative and the other positive, so and \r
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\n" ); document.write( "\n" ); document.write( "So to begin, let's start by letting \r
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\n" ); document.write( "\n" ); document.write( "In order for this to be true, the following things need to be true:\r
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\n" ); document.write( "\n" ); document.write( "Now, if \ 0\">, then \ 0\"> which means that, in order for the sum to be a positive 12, q has to be a positive number greater than 12. Since the only positive choices we have for are 1, 2, and 4, \ 0\"> is not possible and we know that or or \r
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\n" ); document.write( "\n" ); document.write( "If , then and so \r
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\n" ); document.write( "\n" ); document.write( "If , then and so \r
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\n" ); document.write( "\n" ); document.write( "If , then and so \r
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\n" ); document.write( "My calculator said it, I believe it, that settles it
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