document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=133068>Question 133068</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/003052217x/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> how whould i set up an equation for this word problem <BR>\n" );
document.write( "four years ago, katie was twice as old as anne was then. in 6 years, anne will be the same age that katie is now. 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 #97288 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=97288\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Katie's age now: k<BR>\n" );
document.write( "Anne's age now: a\r<BR>\n" );
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document.write( "Katie's age 4 years ago: k - 4<BR>\n" );
document.write( "Anne's age 4 years ago: a - 4\r<BR>\n" );
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document.write( "Anne's age 6 years from now: a + 6\r<BR>\n" );
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document.write( "Four years ago, katie was twice as old as Anne was then:  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k-4=2%28a-4%29 ALIGN=MIDDLE  ALT=\"k-4=2%28a-4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "In 6 years Anne will be the same age as Katie is now: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=a%2B6 ALIGN=MIDDLE  ALT=\"k=a%2B6\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k-4=2%28a-4%29 ALIGN=MIDDLE  ALT=\"k-4=2%28a-4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k-4=2a-8 ALIGN=MIDDLE  ALT=\"k-4=2a-8\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k-2a=-4 ALIGN=MIDDLE  ALT=\"k-2a=-4\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Since we know that  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=a%2B6 ALIGN=MIDDLE  ALT=\"k=a%2B6\"   DISABLED_style= \"max-width:90%; height:auto;\" >, we can substitute:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cartoon%28red%28k%29-2a=-4%2Cred%28%28a%2B6%29%29-2a=-4%29 ALIGN=MIDDLE  ALT=\"cartoon%28red%28k%29-2a=-4%2Cred%28%28a%2B6%29%29-2a=-4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Collect like terms:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a-2a=-4-6 ALIGN=MIDDLE  ALT=\"a-2a=-4-6\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-a=-10 ALIGN=MIDDLE  ALT=\"-a=-10\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Multiply both sides by -1:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a=10 ALIGN=MIDDLE  ALT=\"a=10\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=a%2B6=10%2B6=16 ALIGN=MIDDLE  ALT=\"k=a%2B6=10%2B6=16\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "So Katie is 16 and Anne is 10.\r<BR>\n" );
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document.write( "Check:<BR>\n" );
document.write( "Four years ago, katie was twice as old as Anne was then:\r<BR>\n" );
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document.write( "16 - 4 = 12 <BR>\n" );
document.write( "2 * (10 - 4) = 2 * 6 = 12\r<BR>\n" );
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document.write( "In 6 years Anne will be the same age as Katie is now:\r<BR>\n" );
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document.write( "10 + 6 = 16\r<BR>\n" );
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document.write( "Answer checks.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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