document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=141359>Question 141359</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 using a system of two linear equations in two variables?\r<BR>\n" );
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document.write( "Barry is 8 years older than his sister.  In 3 years, he will be twice as old as she will be then.  How old is each now? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #103001 by </B><A HREF=/tutors/aboutme.mpl?userid=nabla><B>nabla(475)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nabla><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=103001\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> This would be the system of equations I would come up with:\r<BR>\n" );
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document.write( "b=s+8    read as b is s plus 8<BR>\n" );
document.write( "b+3=2(s+3)    read as 3 more than b is 2 times 3 more than s\r<BR>\n" );
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document.write( "Solve by substituting the solution for b in the first equation into the second.<BR>\n" );
document.write( "That is done as follows:\r<BR>\n" );
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document.write( "s+8+3=2s+6<BR>\n" );
document.write( "5=s\r<BR>\n" );
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document.write( "This means that Barry's sister is 5 years old.\r<BR>\n" );
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document.write( "Now, to find Barry's age we plug in s=5 into the first equation:\r<BR>\n" );
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document.write( "b=5+8=13. Barry is 13.\r<BR>\n" );
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document.write( "Let's check this:\r<BR>\n" );
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document.write( "Is Barry currently 8 years older than his sister who is 5? Yes, 5+8=13.<BR>\n" );
document.write( "In 3 years, will Barry be twice as old as his sister? 5+3=8; 13+3=16; 2(8)=16; Yes. </SPAN>\n" );
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