document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1042857>Question 1042857</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a, b, n &#8712; Z with n > 1. Prove that if a &#8801; b (mod n) then 2a &#8801; 2b (mod n). </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #657983 by </B><A HREF=/tutors/aboutme.mpl?userid=rothauserc><B>rothauserc(4718)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rothauserc><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/cgi-bin/show-face.mpl?user=rothauserc><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=657983\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a congruent to b modulus n means that a-b is divisible by n<BR>\n" );
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document.write( "then we have<BR>\n" );
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document.write( "a - b = nc where c is an integer<BR>\n" );
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document.write( "then we have<BR>\n" );
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document.write( "a = b + nc<BR>\n" );
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document.write( "multiply both sides of the = by 2<BR>\n" );
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document.write( "2a = 2b + 2nc<BR>\n" );
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document.write( "we have a, b, n, c are integers, then<BR>\n" );
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document.write( "2c is an integer say p, then<BR>\n" );
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document.write( "2a = 2b + np = 2b mod n<BR>\n" );
document.write( "We are done<BR>\n" );
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document.write( ":\r<BR>\n" );
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document.write( " </SPAN>\n" );
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