document.write( "Question 658497: x^2-4x=21
\n" ); document.write( "solve for x \n" ); document.write( "

Algebra.Com's Answer #410307 by checkley79(3341) $\"\"$ $\"About$

You can put this solution on YOUR website!
x^2-4x=21
\n" ); document.write( "X^2-4X-21=0
\n" ); document.write( "(X-7)(X+3)=0
\n" ); document.write( "X-7=0
\n" ); document.write( "X=7 ANS.
\n" ); document.write( "X+3=0
\n" ); document.write( "X=-3 ANS.
\n" ); document.write( "PROOFS:
\n" ); document.write( "-7^2-4*-7=21
\n" ); document.write( "49+28=21
\n" ); document.write( "21=21
\n" ); document.write( "-3^2-4*-3=21
\n" ); document.write( "9+12=21
\n" ); document.write( "21=21 \n" ); document.write( "

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