document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=476093>Question 476093</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Dear math teacher, \r<BR>\n" );
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document.write( "I am having difficulties with the following problem: <BR>\n" );
document.write( "(a)Find n; (b) n cannot equal to .... integers. <BR>\n" );
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document.write( "(n+2)Cn = 45<BR>\n" );
document.write( "(n+2)(n+1)n!/(2.1)n! = 45 and after canceling n! we get <BR>\n" );
document.write( "(n+2)(n+1) = 90<BR>\n" );
document.write( "n^2 + 3n - 88 = 0<BR>\n" );
document.write( "(n+11)(n-8) = 0<BR>\n" );
document.write( "n = -11 and n = 8\r<BR>\n" );
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document.write( "My answer for (a) is n = 8 only since factorial is not defined for negative numbers. For (b), our n cannot equal -11 and zero since n was canceled out above. Please let me know if my reasoning is correct. \r<BR>\n" );
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document.write( "Thank you very much. \r<BR>\n" );
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document.write( "I. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #326486 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=326486\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You are correct. Good job. You can verify this by plugging in n=8 and evaluating (n+2) C n to get\r<BR>\n" );
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document.write( "(n+2) C n\r<BR>\n" );
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document.write( "(8+2) C 8\r<BR>\n" );
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document.write( "10 C 8\r<BR>\n" );
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document.write( "(10!)/(8!(10-8)!)\r<BR>\n" );
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document.write( "(10*9*8!)/(8!2!)\r<BR>\n" );
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document.write( "(10*9)/(2*1)\r<BR>\n" );
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document.write( "90/2\r<BR>\n" );
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document.write( "45\r<BR>\n" );
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document.write( "So this verifies the answer. </SPAN>\n" );
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