document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1178915>Question 1178915</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Segment AB is trisected at its<BR>\n" );
document.write( "points of intersection with<BR>\n" );
document.write( "concentric circles of radius 7cm<BR>\n" );
document.write( "and 9cm. Find the length of<BR>\n" );
document.write( "segment AB.<BR>\n" );
document.write( "https://media.discordapp.net/attachments/769181283913695264/833885965344440350/unknown.png </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #808389 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=808389\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "Call the center of the circles O.<br><BR>\n" );
document.write( "Let points C and D be the points of intersection of AB with the smaller circle.<br><BR>\n" );
document.write( "Let point E be on AB such that OE is perpendicular to AB.<br><BR>\n" );
document.write( "By symmetry, CE=DE; let that length be x (i.e., CD=2x).<br><BR>\n" );
document.write( "C and D trisect AB, so AC=DB=2x.<br><BR>\n" );
document.write( "Use the Pythagorean Theorem on triangles OED and OEB to get two equations in x^2 and y^2.  Those two equations are easily solved for x, leading immediately to the answer to the problem.<br><BR>\n" );
document.write( "I leave it to you to do the work to finish.<br><BR>\n" );
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