document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=859346>Question 859346</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The centers of two circles are 25 units apart. The radius of one circle is 11 and the radius of the other circle is 4. What is the length of the common external tangent? I'm having trouble with drawing the diagram and starting out the problem. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #517705 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=517705\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let P & Q be the centers of the two circles\r<BR>\n" );
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document.write( "let MN be the tangent to both circles\r<BR>\n" );
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document.write( "Draw PM & QM the radii parallel to each other\r<BR>\n" );
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document.write( "From Q draw a parallel to MN to touch PM at T\r<BR>\n" );
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document.write( "So PTQ is a right triangle\r<BR>\n" );
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document.write( "angle PTQ = 90 \r<BR>\n" );
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document.write( "PQ is the hypotenuse<BR>\n" );
document.write( "which is 25 units<BR>\n" );
document.write( "PT = 11-4 = 7 units\r<BR>\n" );
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document.write( "Using Pytahgoras theorem<BR>\n" );
document.write( "25^-7^2= QT^2\r<BR>\n" );
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document.write( "576=QT^2\r<BR>\n" );
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document.write( "QT=24\r<BR>\n" );
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document.write( "But QT = MN\r<BR>\n" );
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document.write( "there fore MN = 24 units\r<BR>\n" );
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document.write( "Draw the figure you will walk through </SPAN>\n" );
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