document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=388029>Question 388029</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the radius of the circle defined by the equation: x^2+y^2-10x+4y+4=0. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #274338 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20850)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=274338\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Recall the equation of a circle:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x-h%29%5E2%2B%28y-k%29%5E2+=+r%5E2+ ALIGN=MIDDLE  ALT=\"%28x-h%29%5E2%2B%28y-k%29%5E2+=+r%5E2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >where (h,k) is the circle's center and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r+ ALIGN=MIDDLE  ALT=\"r+\"   DISABLED_style= \"max-width:90%; height:auto;\" >is the radius.\r<BR>\n" );
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document.write( "In this problem, we need to complete the square to get the equation in the above form.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2+%2B+y%5E2+-+10x+%2B+4y+%2B+4+=+0 ALIGN=MIDDLE  ALT=\"x%5E2+%2B+y%5E2+-+10x+%2B+4y+%2B+4+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" >.......you just need to realize that you take half of the linear term (x and y)\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x-5%29%5E2+-+25%2B%28y%2B2%29%5E2+-+4+=+-4+ ALIGN=MIDDLE  ALT=\"%28x-5%29%5E2+-+25%2B%28y%2B2%29%5E2+-+4+=+-4+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x-5%29%5E2+%2B%28y%2B2%29%5E2+=+-4+%2B+25+%2B+4 ALIGN=MIDDLE  ALT=\"%28x-5%29%5E2+%2B%28y%2B2%29%5E2+=+-4+%2B+25+%2B+4\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x-5%29%5E2+%2B%28y%2B6%29%5E2+=25 ALIGN=MIDDLE  ALT=\"%28x-5%29%5E2+%2B%28y%2B6%29%5E2+=25\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x-5%29%5E2+%2B%28y%2B6%29%5E2+=+5%5E2 ALIGN=MIDDLE  ALT=\"%28x-5%29%5E2+%2B%28y%2B6%29%5E2+=+5%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >...............<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r%5E2=5%5E2 ALIGN=MIDDLE  ALT=\"r%5E2=5%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >...>....<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=r=5 ALIGN=MIDDLE  ALT=\"r=5\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "It's obvious from above that the center of the circle is (5,-2) and radius is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5 ALIGN=MIDDLE  ALT=\"5\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( " <TR><TD  ALIGN=MIDDLE>Solved by <A  rel=nofollow HREF=http://wiki.algebra.com/index.php/Tutoring_-_pluggable_solvers>pluggable</A> solver: <A  rel=nofollow HREF=Plot_a_circle.solver>PLOT any circle and describe it</A></TD></TR>\n" );
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document.write( "  Diameter:  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d+=+2r+=+2%2A5+=+10 ALIGN=MIDDLE  ALT=\"d+=+2r+=+2%2A5+=+10\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( "  Area:      <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=area+=+pi%5Cr%5E2+=+pi%2A5%5E2+=+78.5398173497349 ALIGN=MIDDLE  ALT=\"area+=+pi%5Cr%5E2+=+pi%2A5%5E2+=+78.5398173497349\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "  Perimeter: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=perimeter+=+2%5Cpi%5Cr+=+2%5Cpi%2A5+=+31.415926939894 ALIGN=MIDDLE  ALT=\"perimeter+=+2%5Cpi%5Cr+=+2%5Cpi%2A5+=+31.415926939894\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%0D%0A++drawing%28+300%2C+300%2C+-10%2C+10%2C+-10%2C+10%2C+%0D%0A++++grid%28+1+%29%2C%0D%0A++++red%28+circle%28+5%2C+-2%2C+5+%29+%29%2C%0D%0A++++blue%28+circle%28+5%2C+-2%2C+0.1+%29+%29%2C%0D%0A++++blue%28+circle%28+5%2C+-2%2C+0.2+%29+%29%0D%0A++%29%0D%0A++ ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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