document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=141369>Question 141369</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0130443980/algebrahomeworkh>Prentice hall algebra 1</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> i need solution.<BR>\n" );
document.write( "In a two digit number the digit at ten place is twice the digit at unit place.on interchanging the digits the number is reduced by 18. find the number. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #103065 by </B><A HREF=/tutors/aboutme.mpl?userid=ptaylor><B>ptaylor(2198)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ptaylor><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=ptaylor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=103065\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x=the 10's digit of the original number<BR>\n" );
document.write( "And let y= the unit's digit of the original number<BR>\n" );
document.write( "The original number is 10x+y; if the digits are reversed, the new number would be 10y+x\r<BR>\n" );
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document.write( "Now we are told that:\r<BR>\n" );
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document.write( "x=2y------------------------------eq1<BR>\n" );
document.write( "and<BR>\n" );
document.write( "10x+y=10y+x+36-----------------------eq2\r<BR>\n" );
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document.write( "substitute x=2y from eq1 into eq2<BR>\n" );
document.write( "10*2y+y=10y+2y+36  simplify\r<BR>\n" );
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document.write( "21y=12y+36  subtract 12y from each side\r<BR>\n" );
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document.write( "21y-12y=12y-12y+36  collect like terms\r<BR>\n" );
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document.write( "9y=36  divide each side by 9\r<BR>\n" );
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document.write( "y=4---------------------------the unit's digit\r<BR>\n" );
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document.write( "substitute y=4 into eq1<BR>\n" );
document.write( "x=2*4=8--------------------------the 10's digit\r<BR>\n" );
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document.write( "So, the number is 84\r<BR>\n" );
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document.write( "CK\r<BR>\n" );
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document.write( "8=2*4<BR>\n" );
document.write( "8=8<BR>\n" );
document.write( "and<BR>\n" );
document.write( "48+36=84<BR>\n" );
document.write( "84=84\r<BR>\n" );
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document.write( "Hope this helps---ptaylor </SPAN>\n" );
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