document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=943086>Question 943086</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello, I am just struggling how to set up the problem. I know how to solve it, it's just forming the equation is what troubles me.\r<BR>\n" );
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document.write( "Bob is 15 years older than his sister. In ten years, Bob will be twice as old as his sister will  be. How old are they now?\r<BR>\n" );
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document.write( "It's a substitution method question. Is the first part x=y + 15? I can't figure out the second half. Please help!!<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #574941 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=574941\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> First, define your variables clearly. What are x and y? To minimize confusion, let b and s be Bob's and her sister's ages now.\r<BR>\n" );
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document.write( "b = s+15 (Bob is 15 years older than his sister)<BR>\n" );
document.write( "b+10 = 2(s+10) (Bob, in 10 years, is twice as hold as his sister, in 10 years)\r<BR>\n" );
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document.write( "Replace b with s+15 in the second equation and solve for s. </SPAN>\n" );
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