document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=286895>Question 286895</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Suppose ABC~JKL with BC=28, JK=12, and KL=42. Find the perimeter of ABC if the perimeter of JKL is 72\r<BR>\n" );
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document.write( "A. 60<BR>\n" );
document.write( "B. 48<BR>\n" );
document.write( "C. 18<BR>\n" );
document.write( "D. 12\r<BR>\n" );
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document.write( "Thank you so much, I am completely clueless on how to work this </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #208043 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=208043\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Since the perimeter of JKL is 72, and we know two sides of JKL, we can easily solve for the missing length JL by remembering that \r<BR>\n" );
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document.write( "Perimeter = side1+side2+side3\r<BR>\n" );
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document.write( "So <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=72=12%2B42%2BJL ALIGN=MIDDLE  ALT=\"72=12%2B42%2BJL\"   DISABLED_style= \"max-width:90%; height:auto;\" >. Solve for JL to get <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=JL=18 ALIGN=MIDDLE  ALT=\"JL=18\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Since ABC~JKL (triangle ABC is similar to triangle JKL), we can set up the ratios:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=AB%2FJK=BC%2FKL ALIGN=MIDDLE  ALT=\"AB%2FJK=BC%2FKL\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=AC%2FJL=BC%2FKL ALIGN=MIDDLE  ALT=\"AC%2FJL=BC%2FKL\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "note: it might help to draw out the triangles to see what's going on.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=AB%2FJK=BC%2FKL ALIGN=MIDDLE  ALT=\"AB%2FJK=BC%2FKL\"   DISABLED_style= \"max-width:90%; height:auto;\" > Start with the first equation\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=AB%2F12=28%2F42 ALIGN=MIDDLE  ALT=\"AB%2F12=28%2F42\"   DISABLED_style= \"max-width:90%; height:auto;\" > Plug in BC=28, JK=12, and KL=42\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=AB%2F12=2%2F3 ALIGN=MIDDLE  ALT=\"AB%2F12=2%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" > Reduce.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=AB=%282%2F3%29%2A12 ALIGN=MIDDLE  ALT=\"AB=%282%2F3%29%2A12\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply both sides by 12\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=AB=24%2F3 ALIGN=MIDDLE  ALT=\"AB=24%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=AB=8 ALIGN=MIDDLE  ALT=\"AB=8\"   DISABLED_style= \"max-width:90%; height:auto;\" > Reduce.\r<BR>\n" );
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document.write( "So one side of ABC is AB = 8\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=AC%2FJL=BC%2FKL ALIGN=MIDDLE  ALT=\"AC%2FJL=BC%2FKL\"   DISABLED_style= \"max-width:90%; height:auto;\" > Move onto the second equation\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=AC%2F18=28%2F42 ALIGN=MIDDLE  ALT=\"AC%2F18=28%2F42\"   DISABLED_style= \"max-width:90%; height:auto;\" > Plug in BC=28, JL=18, and KL=42\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=AC%2F18=2%2F3 ALIGN=MIDDLE  ALT=\"AC%2F18=2%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" > Reduce.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=AC=%282%2F3%29%2A18 ALIGN=MIDDLE  ALT=\"AC=%282%2F3%29%2A18\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply both sides by 18\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=AC=36%2F3 ALIGN=MIDDLE  ALT=\"AC=36%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" > Multiply\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=AC=12 ALIGN=MIDDLE  ALT=\"AC=12\"   DISABLED_style= \"max-width:90%; height:auto;\" > Reduce.\r<BR>\n" );
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document.write( "So the last side of ABC is AC = 12\r<BR>\n" );
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document.write( "Now just add up the sides AB = 8, BC = 28, and AC = 12 to get the perimeter of ABC: \r<BR>\n" );
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document.write( "P = 8+28+12 = 48\r<BR>\n" );
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document.write( "So the perimeter of ABC is 48 units.\r<BR>\n" );
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document.write( "Note: the ratio of the perimeter of ABC to the perimeter of JKL is the same as the ratio of any two corresponding sides. This saves us a lot of work, but it's always good to take the long way so we can see what's going on. </SPAN>\n" );
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