document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=141367>Question 141367</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0130442631/algebrahomeworkh>Prentice hall algebra 1</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> How do I solve by using two equations in two variables?\r<BR>\n" );
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document.write( "Larry is 8 years older than his sister.  In 3 years, he will be twice as old as she is now. How old are they now? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #103018 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=103018\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "Let x=sister's age<BR>\n" );
document.write( "And let y=Larry's age<BR>\n" );
document.write( "y+3=Larry's age 3 years from now\r<BR>\n" );
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document.write( "Now we are told the following:\r<BR>\n" );
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document.write( "y=x+8------------------------------------eq1<BR>\n" );
document.write( "and<BR>\n" );
document.write( "y+3=2x-----------------------------------eq2\r<BR>\n" );
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document.write( "substitute y=x+3 from eq1 into eq2\r<BR>\n" );
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document.write( "x+8+3=2x  subtract x from each side\r<BR>\n" );
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document.write( "x-x+8+3=2x-x  collect like terms\r<BR>\n" );
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document.write( "11=x or<BR>\n" );
document.write( "x=11-------------------------------sister's age now<BR>\n" );
document.write( "substitute into eq1\r<BR>\n" );
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document.write( "y=11+8=19----------------------------Larry's age now\r<BR>\n" );
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document.write( "CK\r<BR>\n" );
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document.write( "19 is 8 years older than 11<BR>\n" );
document.write( "and<BR>\n" );
document.write( "22=2*11<BR>\n" );
document.write( "22=22\r<BR>\n" );
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document.write( "Hope this helps---ptaylor\r<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );