document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=985461>Question 985461</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The points X(3,4) and Y(9,1) lie on the circumference of a circle.  There is exactly 60 degree of arc between X and Y. Find the radius of the circle. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #606270 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39620)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=606270\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The center point of the circle is equally distant from both X and Y, forming an isosceles triangle; but since you have central angle being 60 degrees, this forces the other angles each to also be 60 degrees.  This is then an equilateral triangle with points, X, Y, and the center of the circle.  The radius will be the DISTANCE between  X and Y, found using the distance formula.  Now you know radius r.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=sameAs=sqrt%28%289-3%29%5E2%2B%281-4%29%5E2%29 ALIGN=MIDDLE  ALT=\"r=sameAs=sqrt%28%289-3%29%5E2%2B%281-4%29%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=sqrt%2836%2B9%29 ALIGN=MIDDLE  ALT=\"r=sqrt%2836%2B9%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=sqrt%2845%29 ALIGN=MIDDLE  ALT=\"r=sqrt%2845%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=3sqrt%285%29 ALIGN=MIDDLE  ALT=\"r=3sqrt%285%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Next, simply form <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%286%2F36%29%282pi%2Ar%29 ALIGN=MIDDLE  ALT=\"%286%2F36%29%282pi%2Ar%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > and compute or evaluate the length of arc.<BR>\n" );
document.write( "(Fraction of the circumference) </SPAN>\n" );
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