document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=810677>Question 810677</A>: <I><SPAN STYLE=\"word-break: break-all;\"> find the equation of a circle of radius 'a' which passes through the two points on the axis of x which are at a distance b from origin<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 #488339 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39625)</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=488339\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If both x-intercepts are b distance from the Origin, then looking at a picture or graph of this circle should show that the center is on the y-axis.  Can you identify an isosceles triangle? \r<BR>\n" );
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document.write( "The center is some point, (0, c), and since you have a variable for radius, you may have a circle, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x%5E2%29%2B%28y-c%29%5E2=a%5E2 ALIGN=MIDDLE  ALT=\"%28x%5E2%29%2B%28y-c%29%5E2=a%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >.  We really do not know if c is positive or if c is negative.  We should try to obtain an equation in terms of b, but not with the variable c.\r<BR>\n" );
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document.write( "We know two points which are on the circle are (-b,0) and (b,0).<BR>\n" );
document.write( "Either one, x^2 will be positive.<BR>\n" );
document.write( "Use the point(s) in the equation:  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b%5E2%2B%280-c%29%5E2=a%5E2 ALIGN=MIDDLE  ALT=\"b%5E2%2B%280-c%29%5E2=a%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b%5E2%2Bc%5E2=a%5E2 ALIGN=MIDDLE  ALT=\"b%5E2%2Bc%5E2=a%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=c%5E2=a%5E2-b%5E2 ALIGN=MIDDLE  ALT=\"c%5E2=a%5E2-b%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=c=sqrt%28a%5E2-b%5E2%29 ALIGN=MIDDLE  ALT=\"c=sqrt%28a%5E2-b%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, using the positive square root just to be simple.\r<BR>\n" );
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document.write( "Putting this c into the equation,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28x%5E2%2B%28y-sqrt%28a%5E2-b%5E2%29%29%5E2=a%5E2%29 ALIGN=MIDDLE  ALT=\"highlight%28x%5E2%2B%28y-sqrt%28a%5E2-b%5E2%29%29%5E2=a%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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