document.write( "Question 117397: How do i make an appropriate substitution?(y-10/y)^2 -6(y-10/y)-27=0 \n" ); document.write( "

Algebra.Com's Answer #85421 by edjones(8007) $\"\"$ $\"About$

You can put this solution on YOUR website!
(y-10/y)^2 -6(y-10/y)-27=0
\n" ); document.write( "Let (y-10/y)=x
\n" ); document.write( "x^2-6x-27=0
\n" ); document.write( "(x-9)(x+3)=0
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\n" ); document.write( "y-10/y-9=0 substitute (y-10/y) back in for x.
\n" ); document.write( "y^2-10-9y=0 Multiply each side times y to eliminate fraction.
\n" ); document.write( "y^2-9y-10=0
\n" ); document.write( "(y-10)(y+1)=0
\n" ); document.write( ".
\n" ); document.write( "y-10/y+3=0
\n" ); document.write( "y^2-10+3y=0
\n" ); document.write( "y^2+3y-10=0
\n" ); document.write( "(y+5)(y-2)=0
\n" ); document.write( ".
\n" ); document.write( "y=10, y=-1, y=-5, y=2
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\n" ); document.write( "you can also solve this by graphing.
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\n" ); document.write( "Ed
\n" ); document.write( " $\"graph%28500%2C500%2C-8%2C12%2C-1500%2C200%2Cx%5E4-6x%5E3-47x%5E2%2B60x%2B100%29\"$ \n" ); document.write( "

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