document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=43724>Question 43724</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 10.<BR>\n" );
document.write( " Adult tickets for a play cost $11 and child tickets cost $10.  If there were 23 people at a performance and the theater collected $246 from ticket sales, how many children attended the play?\r<BR>\n" );
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document.write( " A)  8 children    B)  16 children    C)  7 children    D)  6 children<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 #28707 by </B><A HREF=/tutors/aboutme.mpl?userid=aaaaaaaa><B>aaaaaaaa(138)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=aaaaaaaa><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=28707\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Number of adults = a<BR>\n" );
document.write( "Number of children = c\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a+%2B+c+=+23 ALIGN=MIDDLE  ALT=\"a+%2B+c+=+23\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=11a+%2B+10c+=+246 ALIGN=MIDDLE  ALT=\"11a+%2B+10c+=+246\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( " <TR><TD  ALIGN=MIDDLE>Solved by <A  rel=nofollow HREF=http://wiki.algebra.com/index.php/Tutoring_-_pluggable_solvers>pluggable</A> solver: <A  rel=nofollow HREF=linear_substitution.solver>SOLVE linear system by SUBSTITUTION</A></TD></TR>\n" );
document.write( "<TR><TD  ALIGN=LEFT>Solve:<BR>\n" );
document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+system%28+%0D%0A++++1%5Ca+%2B+1%5Cc+=+23%2C%0D%0A++++11%5Ca+%2B+10%5Cc+=+246+%29%0D%0A++ ALIGN=MIDDLE  ALT=\"+system%28+%0D%0A++++1%5Ca+%2B+1%5Cc+=+23%2C%0D%0A++++11%5Ca+%2B+10%5Cc+=+246+%29%0D%0A++\"   DISABLED_style= \"max-width:90%; height:auto;\" >We'll use substitution. After moving 1*c to the right, we get:<BR>\n" );
document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2Aa+=+23+-+1%2Ac ALIGN=MIDDLE  ALT=\"1%2Aa+=+23+-+1%2Ac\"   DISABLED_style= \"max-width:90%; height:auto;\" >, or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a+=+23%2F1+-+1%2Ac%2F1 ALIGN=MIDDLE  ALT=\"a+=+23%2F1+-+1%2Ac%2F1\"   DISABLED_style= \"max-width:90%; height:auto;\" >. Substitute that<BR>\n" );
document.write( "  into another equation:<BR>\n" );
document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=11%2A%2823%2F1+-+1%2Ac%2F1%29+%2B+10%5Cc+=+246 ALIGN=MIDDLE  ALT=\"11%2A%2823%2F1+-+1%2Ac%2F1%29+%2B+10%5Cc+=+246\"   DISABLED_style= \"max-width:90%; height:auto;\" > and simplify: So, we know that c=7. Since <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a+=+23%2F1+-+1%2Ac%2F1 ALIGN=MIDDLE  ALT=\"a+=+23%2F1+-+1%2Ac%2F1\"   DISABLED_style= \"max-width:90%; height:auto;\" >, a=16.<BR>\n" );
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document.write( "  Answer: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28+a=16%2C+c=7+%29 ALIGN=MIDDLE  ALT=\"system%28+a=16%2C+c=7+%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
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