document.write( "Question 381285: Solve: 8(3x+5)^2 +2(3x+5)-1=0 \n" ); document.write( "

Algebra.Com's Answer #270435 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"u=3x%2B5\"$
\n" ); document.write( " $\"8u%5E2%2B2u-1=0\"$
\n" ); document.write( " $\"%284u-1%29%282u%2B1%29=0\"$
\n" ); document.write( "Two solutions:
\n" ); document.write( " $\"4u-1=0\"$
\n" ); document.write( " $\"4u=1\"$
\n" ); document.write( " $\"u=1%2F4\"$
\n" ); document.write( " $\"3x%2B5=1%2F4\"$
\n" ); document.write( " $\"12x%2B20=1\"$
\n" ); document.write( " $\"12x=19\"$
\n" ); document.write( " $\"highlight%28x=19%2F12%29\"$
\n" ); document.write( ".
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\n" ); document.write( ".
\n" ); document.write( " $\"2u%2B1=0\"$
\n" ); document.write( " $\"2u=-1\"$
\n" ); document.write( " $\"u=-1%2F2\"$
\n" ); document.write( " $\"3x%2B5=-1%2F2\"$
\n" ); document.write( " $\"6x%2B10=-1\"$
\n" ); document.write( " $\"6x=11\"$
\n" ); document.write( " $\"highlight%28x=11%2F6%29\"$
\n" ); document.write( ".
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\n" ); document.write( " \n" ); document.write( "

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