document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=377852>Question 377852</A>: <I><SPAN STYLE=\"word-break: break-all;\"> sue and david are siblings their combined age is 22 sue is four years old than david how old are sue and david </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #268470 by </B><A HREF=/tutors/aboutme.mpl?userid=sophxmai><B>sophxmai(62)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=sophxmai><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=sophxmai><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=268470\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Sue and David are siblings, their combined age is 22. Sue is four years older than David, how old are Sue and David.\r<BR>\n" );
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document.write( "If Sue and David's ages combined equal 22,<BR>\n" );
document.write( "then let 22=x+y. (x is David's age, y is Sue's age)\r<BR>\n" );
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document.write( "To solve this, we should make it so that there's only one variable to solve for.\r<BR>\n" );
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document.write( "Since Sue is 4 years older than David,<BR>\n" );
document.write( "then let x be David's age and (x+4) be Sue's age.\r<BR>\n" );
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document.write( "Now, lets look at our facts.\r<BR>\n" );
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document.write( "22=x+y<BR>\n" );
document.write( "x is David's age<BR>\n" );
document.write( "y is Sue's age<BR>\n" );
document.write( "x+4 is Sue's age\r<BR>\n" );
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document.write( "From here, we can conclude that y=x+4.<BR>\n" );
document.write( "So from 22=x+y, we can substitute y for y=x+4.\r<BR>\n" );
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document.write( "22=x+y<BR>\n" );
document.write( "22=x+(x+4)<BR>\n" );
document.write( "22=2x+4\r<BR>\n" );
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document.write( "Now, solve for x.\r<BR>\n" );
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document.write( "22=2x+4<BR>\n" );
document.write( "18=2x<BR>\n" );
document.write( "9=x\r<BR>\n" );
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document.write( "Now, we have figured out David's age since x stands for David's age.<BR>\n" );
document.write( "To solve for Sue's age, plug in 9=x for y=x+4\r<BR>\n" );
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document.write( "y=x+4<BR>\n" );
document.write( "y=(9)+4<BR>\n" );
document.write( "y=13\r<BR>\n" );
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document.write( "Now, we have found out Sue's age.\r<BR>\n" );
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document.write( "To recap, David is 9 years old and Sue is 13 years old. </SPAN>\n" );
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