document.write( "Question 174078: some students simplify 2x^2-32/x-4 as 2x-8/x-4 =2x-8. choose values of x to mshow this is not true. Then simplify it correctly. \n" ); document.write( "

Algebra.Com's Answer #129077 by ptaylor(2198) $\"\"$ $\"About$

You can put this solution on YOUR website!
You need to use parens to define your problem. I could just as easily read your problem as: 2x^2 - (32/x) - 4
\n" ); document.write( "Show that 2x-8 is not correct:
\n" ); document.write( "Let x=1, then
\n" ); document.write( "(2x^2-32)/(x-4)=(2-32)/(1-4)=-30/-3=10;
\n" ); document.write( "2x-8=2*1-8=-6
\n" ); document.write( "-6 does not equal 10\r
\n" ); document.write( "\n" ); document.write( "Simplify correctly:
\n" ); document.write( "(2x^2-32)/(x-4)=2(x^2-16)/(x-4);
\n" ); document.write( "(x^2-16)=(x+4)(x-4), so
\n" ); document.write( "(2x^2-32)/(x-4)=(2(x+4)(x-4))/(x-4); the (x-4)'s cancel
\n" ); document.write( "and we have:
\n" ); document.write( "2(x+4)=2x+8\r
\n" ); document.write( "\n" ); document.write( "does this help????---ptaylor \n" ); document.write( "

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