document.write( "Question 427273: find the value of r if c(18,r)=c(18,r+2) \n" ); document.write( "

Algebra.Com's Answer #297141 by robertb(5830) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"c%2818%2Cr%29=c%2818%2Cr%2B2%29\"$
\n" ); document.write( "<==> $\"%2818%21%29%2F%28%2818-r%29%21r%21%29+=+%2818%21%29%2F%28%2816-r%29%21%28r%2B2%29%21%29\"$
\n" ); document.write( "<==> $\"1%2F%28%2818-r%29%21r%21%29+=+1%2F%28%2816-r%29%21%28r%2B2%29%21%29\"$
\n" ); document.write( "<==> $\"1%2F%28%2818-r%29%2817+-+r%29%29+=+1%2F%28%28r%2B1%29%28r%2B2%29%29\"$
\n" ); document.write( "<==> $\"%2818-r%29%2817+-+r%29=++%28r%2B1%29%28r%2B2%29\"$
\n" ); document.write( "<==> $\"306-35r+%2B+r%5E2+=+r%5E2+%2B+3r+%2B+2\"$
\n" ); document.write( "<==> 304 = 38r ==> r = 8. \n" ); document.write( "

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