document.write( "Question 15507: factor each trinomial using trail and error.15x^2-x-2 \n" ); document.write( "

Algebra.Com's Answer #7686 by Earlsdon(6294) $\"\"$ $\"About$

You can put this solution on YOUR website!
Factoring trinomials can entail a lot of educated guess-and-check work.\r
\n" ); document.write( "\n" ); document.write( "Factor:\r
\n" ); document.write( "\n" ); document.write( " $\"15x%5E2+-+x+-+2\"$ What are the possible factors of the $\"x%5E2\"$ term?\r
\n" ); document.write( "\n" ); document.write( "1) (15x)(x) or (-15x)(-x)
\n" ); document.write( "2) (5x)(3x) or (-5x)(-3x)\r
\n" ); document.write( "\n" ); document.write( "What are the possible factors of the constant term?\r
\n" ); document.write( "\n" ); document.write( "1) (1)(-2) or (-1)(2)\r
\n" ); document.write( "\n" ); document.write( "What combintation will give the x-term coefficient of -1?\r
\n" ); document.write( "\n" ); document.write( "1) (3)(-2) + (5)(1) This looks promising!
\n" ); document.write( "2) (-3)(2) + (5)(1) This won't do because you need to get a -2 as a constant term.\r
\n" ); document.write( "\n" ); document.write( "So, try:\r
\n" ); document.write( "\n" ); document.write( " $\"%285x+-+2%29%283x+%2B+1%29\"$ Check it out using FOIL.\r
\n" ); document.write( "\n" ); document.write( " $\"%285x+-+2%29%283x+%2B+1%29+=+15x%5E2+%2B+5x+-+6x+-+2\"$ = $\"15x%5E2+-x+-2\"$ \r
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