document.write( "Question 550665: I need to expand this quadratic equation:\r
\n" ); document.write( "\n" ); document.write( "(3r+8)^2\r
\n" ); document.write( "\n" ); document.write( "I answered 3r^2-+2(8*3)+64 ,but it was counted wrong.\r
\n" ); document.write( "\n" ); document.write( "Could anyone help me? \n" ); document.write( "

Algebra.Com's Answer #358977 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"+%283r%2B8%29%5E2+\"$
\n" ); document.write( " $\"+9r%5E2+%2B+24r+%2B+24r+%2B+64+\"$
\n" ); document.write( " $\"+9r%5E2+%2B+48r+%2B+64+\"$ answer
\n" ); document.write( "----------------------
\n" ); document.write( "There's a very simple way to check this
\n" ); document.write( "Pick a small prime number like 13
\n" ); document.write( "and say $\"+r+=+13+\"$
\n" ); document.write( " $\"+%28+3r+%2B+8+%29%5E2+=+%28+39+%2B+8+%29%5E2+\"$
\n" ); document.write( " $\"+47%5E2+=+2209+\"$
\n" ); document.write( "and
\n" ); document.write( " $\"+9r%5E2+%2B+48r+%2B+64+=+9%2A13%5E2+%2B+48%2A13+%2B+64+\"$
\n" ); document.write( " $\"+1521+%2B+624+%2B+64+=+2209+\"$
\n" ); document.write( "OK\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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