document.write( "Question 920749: 12x^2-29x+15=0 ( Factor) \n" ); document.write( "
Algebra.Com's Answer #558554 by josgarithmetic(39617)\"\" \"About 
You can put this solution on YOUR website!
Try thinking of the quadratic trinomial this way.\r
\n" ); document.write( "\n" ); document.write( "\"%28ax%2Bb%29%28cx%2Bd%29=12x%5E2-29%2B15\"
\n" ); document.write( "\"ac%2Ax%5E2%2Bbcx%2Badx%2Bbd\"
\n" ); document.write( "\"ac%2Ax%5E2%2B%28bc%2Bad%29x%2Bbd\"\r
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\n" ); document.write( "\n" ); document.write( "Compare the coefficients to form the equations:
\n" ); document.write( "ac=12, -29=bc+ad, bd=15
\n" ); document.write( "Three equations but FOUR unknown variables. You at least expect a,b,c,d to all be integers, and be nonzero.\r
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\n" ); document.write( "\n" ); document.write( "You can make logical trials and test them.
\n" ); document.write( "a and c not relying on order nor sign, would be one of 1 & 12; 2 &6, 3 & 4.
\n" ); document.write( "b and d similarly would be one of 1 & 15, or 3 & 5.\r
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\n" ); document.write( "\n" ); document.write( "Do what you are able with those facts.\r
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\n" ); document.write( "\n" ); document.write( "A more advanced way to factorize is to use the discriminant:
\n" ); document.write( "\"%28-29%29%5E2-4%2A12%2A15=121\",
\n" ); document.write( "\"121=highlight%2811%5E2%29\";
\n" ); document.write( "This means that the ROOTS for x are \"%2829-11%29%2F24\" and \"%2829%2B11%29%2F24\";
\n" ); document.write( "or, \"18%2F24=3%2F4\" and \"40%2F24=8%2F3\";
\n" ); document.write( "This then means you can choose a form for your quadratic expression,
\n" ); document.write( "\"highlight%2812%28x-3%2F4%29%28x-8%2F3%29%29\", which you could refactor if you want to.
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