document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=535696>Question 535696</A>: <I><SPAN STYLE=\"word-break: break-all;\"> how do I solve this problem by method of addition and substitution:\r<BR>\n" );
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document.write( "A toll bridge costs $2. If you use the bridge x times in a month, the monthly cost , y is y=2x. With a $10 coupon book the toll is redueced $1. The monthly cost, y, of using coupon book is y=x+10.  How many times do use the bridge without the coupon book to to equal the cost with the coupon book.<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 #351968 by </B><A HREF=/tutors/aboutme.mpl?userid=Earlsdon><B>Earlsdon(6294)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Earlsdon><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=351968\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You have the cost equations for both situations, so set these two equations equal to each other and solve for x.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+2x ALIGN=MIDDLE  ALT=\"y+=+2x\"   DISABLED_style= \"max-width:90%; height:auto;\" > and<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+x%2B10 ALIGN=MIDDLE  ALT=\"y+=+x%2B10\"   DISABLED_style= \"max-width:90%; height:auto;\" > Set these equal.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2x+=+x%2B10 ALIGN=MIDDLE  ALT=\"2x+=+x%2B10\"   DISABLED_style= \"max-width:90%; height:auto;\" > Solve for x. Subtract x from both sides.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x+=+10 ALIGN=MIDDLE  ALT=\"x+=+10\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The monthly cost, y, will be the same if you use the bridge 10 times.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%2810%29+=+10%2B10 ALIGN=MIDDLE  ALT=\"2%2810%29+=+10%2B10\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20+=+20 ALIGN=MIDDLE  ALT=\"20+=+20\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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