document.write( "Question 94754: Factor the polynomial completely.\r
\n" ); document.write( "\n" ); document.write( "I have factored other polynomials, but this one confuses me. The equation is...
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\n" ); document.write( "-3s^2-10s+8\r
\n" ); document.write( "\n" ); document.write( "Thank you very much for your time!
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Algebra.Com's Answer #68997 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
Given:
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\n" ); document.write( "\"-3s%5E2-10s%2B8\"
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\n" ); document.write( "To factor this, you make things a little easier by factoring out -1. If you do this the
\n" ); document.write( "result is:
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\n" ); document.write( "\"%28-1%29%2A%283s%5E2+%2B+10s+-+8%29\"
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\n" ); document.write( "Let's not forget the -1 factor, but let's now concentrate on factoring the polynomial \"3s%5E2%2B10s-8\".
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\n" ); document.write( "Since the 3 preceding the s-squared term can only be factored into 3 and 1 we know if the
\n" ); document.write( "polynomial can be factored, the factors must be of the form:
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\n" ); document.write( "\"%283s+%2B-+a+%29%28s+%2B-+b+%29\"
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\n" ); document.write( "where \"a\" and \"b\" must be a factor pair of 8 ... in other words \"a\" and \"b\" must be either
\n" ); document.write( "4 and 2 or 8 and 1. And, considering the signs of \"a\" and \"b\", the terms must multiply with
\n" ); document.write( "3 and 1 to result in the middle value + 10. After some thought, you might see that if
\n" ); document.write( "\"b\" were +4 and \"a\" were -2, the factors would become:
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\n" ); document.write( "\"%283s+-2%29%28s+%2B+4%29\"
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\n" ); document.write( "The cross product of +4 times +3s is +12s. And the cross product of -2 and s is -2s. These
\n" ); document.write( "cross products combine to give +12s - 2s = +10s which is the middle term of the polynomial
\n" ); document.write( "being factored.
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\n" ); document.write( "But don't forget that we originally factored a -1 from the polynomial. Therefore, when
\n" ); document.write( "we put that factor into the solution the answer becomes:
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\n" ); document.write( "\"%28-1%29%2A%283s+-+2%29%28+s+%2B+4%29\"
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\n" ); document.write( "and by convention, the \"1\" is understood so the answer is just:
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\n" ); document.write( "\"-%283s-2%29%28s%2B4%29\"
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\n" ); document.write( "This is the answer. You could also move the minus sign into one set of parentheses.
\n" ); document.write( "For example, you could have the answer in the form:
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\n" ); document.write( "\"%283s-2%29%28-s-4%29\"
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\n" ); document.write( "and if you multiply this out you will get back to the original polynomial you were given
\n" ); document.write( "to factor.
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\n" ); document.write( "Hope that this helps you to understand the way to get to an answer for this problem.
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