document.write( "Question 289931: I'm looking for the answer to the question\r
\n" ); document.write( "\n" ); document.write( "x^4-81x^2=0\r
\n" ); document.write( "\n" ); document.write( "I know it's GCF but what is the answer? \n" ); document.write( "

Algebra.Com's Answer #209885 by Earlsdon(6294) $\"\"$ $\"About$

You can put this solution on YOUR website!
Solve for x: There will be four solutions.
\n" ); document.write( " $\"x%5E4-81x%5E2+=+0\"$ Factor $\"x%5E2\"$
\n" ); document.write( " $\"x%5E2%28x%5E2-81%29+=+0\"$ Apply the zero product rule:
\n" ); document.write( " $\"x%5E2+=+0\"$ or $\"x%5E2-81+=+0\"$ so
\n" ); document.write( " $\"x+=+0\"$
\n" ); document.write( " $\"x+=+0\"$
\n" ); document.write( " $\"x+=+9\"$
\n" ); document.write( " $\"x+=+-9\"$ \n" ); document.write( "

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