document.write( "Question 26290: how do you solve the Qudadratic Expression 16x^2-80x-12 \n" ); document.write( "

Algebra.Com's Answer #14199 by longjonsilver(2297) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"16x%5E2-80x-12\"$
\n" ); document.write( " $\"+4%284x%5E2-20x-3%29+\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"+4%284x%5E2-20x-3%29+\"$ . I cannot see this factorising easily, so resort to the quadratic formula.\r
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\n" ); document.write( "\n" ); document.write( " $\"x+=+%28-b+%2B-+sqrt%28b%5E2+-+4ac%29%29%2F%282a%29\"$
\n" ); document.write( " $\"x+=+%28-%28-80%29+%2B-+sqrt%28%28-80%29%5E2+-+4%2816%29%28-12%29%29%29%2F%282%2816%29%29\"$
\n" ); document.write( " $\"x+=+%2880+%2B-+sqrt%286400+%2B+768%29%29%2F%2832%29\"$
\n" ); document.write( " $\"x+=+%2880+%2B-+sqrt%287168%29%29%2F%2832%29\"$ \r
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\n" ); document.write( "\n" ); document.write( "Now to try to simplify the square root. Start with an easy pair of factors like 4*1792 and build up to 16*448 etc, until you end up with a primary number... like the 7 below.\r
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\n" ); document.write( "\n" ); document.write( " $\"x+=+%2880+%2B-+sqrt%281024%2A7%29%29%2F%2832%29\"$
\n" ); document.write( " $\"x+=+%2880+%2B-+sqrt%281024%29sqrt%287%29%29%2F%2832%29\"$
\n" ); document.write( " $\"x+=+%2880+%2B-+32sqrt%287%29%29%2F%2832%29\"$
\n" ); document.write( " $\"x+=+%2880+%2B+32sqrt%287%29%29%2F%2832%29\"$ OR $\"x+=+%2880+-+32sqrt%287%29%29%2F%2832%29\"$
\n" ); document.write( " $\"x+=+%282.5+%2B+sqrt%287%29%29\"$ OR $\"x+=+%282.5+-+sqrt%287%29%29\"$ \r
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\n" ); document.write( "\n" ); document.write( "jon.
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