document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=458720>Question 458720</A>: <I><SPAN STYLE=\"word-break: break-all;\">  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #314675 by </B><A HREF=/tutors/aboutme.mpl?userid=math-vortex><B>math-vortex(648)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math-vortex><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=math-vortex><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=314675\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "Explanation:<BR>\n" );
document.write( "This is a problem about ratios and proportions. Similar triangles have the same shape, but they are shrunk or enlarged (like on a copy machine.) \r<BR>\n" );
document.write( "\n" );
document.write( "Important Math Fact: Corresponding sides of two similar triangles are proportional to each other. This means that the ratio of the shortest sides of the two triangles is equal to the ratio of the longest sides of the triangles.\r<BR>\n" );
document.write( "\n" );
document.write( "The shortest sides are 3 and 12. Their ratio is 3/12=1/4.<BR>\n" );
document.write( "The two longest sides will also have a ratio of 1/4.<BR>\n" );
document.write( "The longest side of the small triangle is 5. <BR>\n" );
document.write( "If L is the length of the longest side of the big triangle, then we set up a ratio like this:<BR>\n" );
document.write( "5/L=1/4.<BR>\n" );
document.write( "Solving for L, we get L=20.<BR>\n" );
document.write( "The longest side is 20 units. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );