document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=768538>Question 768538</A>: <I><SPAN STYLE=\"word-break: break-all;\"> two circles  radii a&b(a>b) touch each other externally.St is a common tangent touching the circles at S&T respectively. then ST^2=?<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 #468347 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=468347\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The radii of the circle are a & b a>b\r<BR>\n" );
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document.write( "The distance between their centers = a+b\r<BR>\n" );
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document.write( "a tangent drawn from the smaller circle parallel to the above line will be  equal to (a+b)\r<BR>\n" );
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document.write( "a-b is the difference between the two radii\r<BR>\n" );
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document.write( "ST^2 = (a+b)^2+(a-b)^2\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ST%5E2+=+a%5E2%2B2ab%2Bb%5E2%2Ba%5E2-2ab%2Bb%5E2 ALIGN=MIDDLE  ALT=\"ST%5E2+=+a%5E2%2B2ab%2Bb%5E2%2Ba%5E2-2ab%2Bb%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "ST^2= 2(a^2+b^2) </SPAN>\n" );
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