document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1026883>Question 1026883</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find:<BR>\n" );
document.write( "a) (h,k) and radius r<BR>\n" );
document.write( "b) Graph the circle<BR>\n" );
document.write( "c) Find intercepts, if any\r<BR>\n" );
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document.write( "(x^2)+(y^2)+x+y-(1/2)=0 or (x^2)+x+(y^2)+y=(1/2)<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 #642294 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=642294\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find:<BR>\n" );
document.write( "a) (h,k) and radius r<BR>\n" );
document.write( "b) Graph the circle\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "(x^2)+(y^2)+x+y-(1/2)=0 or (x^2)+x+(y^2)+y=(1/2)<BR>\n" );
document.write( "===========<BR>\n" );
document.write( "x^2+x+y^2+y=1/2<BR>\n" );
document.write( "Complete the squares for x and y<BR>\n" );
document.write( "x^2+x+1/4 + y^2+y+1/4 = 1/2+1/4+1/4 = 1<BR>\n" );
document.write( "(x+1/2)^2 + (y+1/2)^2 = 1<BR>\n" );
document.write( "(h,k) = (-1/2,-1/2)<BR>\n" );
document.write( "r = 1<BR>\n" );
document.write( "-------------<BR>\n" );
document.write( "c) Find intercepts, if any<BR>\n" );
document.write( "x^2+x+y^2+y=1/2<BR>\n" );
document.write( "y = 0 --> x^2 + x - 1/2 = 0<BR>\n" );
document.write( "<TABLE  BORDER=1>\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=solve_quadratic_equation.solver>SOLVE quadratic equation (work shown, graph etc)</A></TD></TR>\n" );
document.write( "<TR><TD  ALIGN=LEFT>Quadratic equation <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ax%5E2%2Bbx%2Bc=0 ALIGN=MIDDLE  ALT=\"ax%5E2%2Bbx%2Bc=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > (in our case <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1x%5E2%2B1x%2B-0.5+=+0 ALIGN=MIDDLE  ALT=\"1x%5E2%2B1x%2B-0.5+=+0\"   DISABLED_style= \"max-width:90%; height:auto;\" >) has the following solutons:<BR>\n" );
document.write( "  <BR>\n" );
document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca ALIGN=MIDDLE  ALT=\"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "  <BR>\n" );
document.write( "  For these solutions to exist, the <U>discriminant</U> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b%5E2-4ac ALIGN=MIDDLE  ALT=\"b%5E2-4ac\"   DISABLED_style= \"max-width:90%; height:auto;\" > should not be a negative number.<BR>\n" );
document.write( "  <BR>\n" );
document.write( "  First, we need to compute the discriminant <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b%5E2-4ac ALIGN=MIDDLE  ALT=\"b%5E2-4ac\"   DISABLED_style= \"max-width:90%; height:auto;\" >: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b%5E2-4ac=%281%29%5E2-4%2A1%2A-0.5=3 ALIGN=MIDDLE  ALT=\"b%5E2-4ac=%281%29%5E2-4%2A1%2A-0.5=3\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( "  <BR>\n" );
document.write( "  Discriminant d=3 is greater than zero. That means that there are two solutions: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+x%5B12%5D+=+%28-1%2B-sqrt%28+3+%29%29%2F2%5Ca ALIGN=MIDDLE  ALT=\"+x%5B12%5D+=+%28-1%2B-sqrt%28+3+%29%29%2F2%5Ca\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( "  <BR>\n" );
document.write( "    <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5B1%5D+=+%28-%281%29%2Bsqrt%28+3+%29%29%2F2%5C1+=+0.366025403784439 ALIGN=MIDDLE  ALT=\"x%5B1%5D+=+%28-%281%29%2Bsqrt%28+3+%29%29%2F2%5C1+=+0.366025403784439\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "    <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5B2%5D+=+%28-%281%29-sqrt%28+3+%29%29%2F2%5C1+=+-1.36602540378444 ALIGN=MIDDLE  ALT=\"x%5B2%5D+=+%28-%281%29-sqrt%28+3+%29%29%2F2%5C1+=+-1.36602540378444\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "    <BR>\n" );
document.write( "    Quadratic expression <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1x%5E2%2B1x%2B-0.5 ALIGN=MIDDLE  ALT=\"1x%5E2%2B1x%2B-0.5\"   DISABLED_style= \"max-width:90%; height:auto;\" > can be factored:<BR>\n" );
document.write( "  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1x%5E2%2B1x%2B-0.5+=+%28x-0.366025403784439%29%2A%28x--1.36602540378444%29 ALIGN=MIDDLE  ALT=\"1x%5E2%2B1x%2B-0.5+=+%28x-0.366025403784439%29%2A%28x--1.36602540378444%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "  Again, the answer is: 0.366025403784439, -1.36602540378444.\n" );
document.write( "Here's your graph:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B1%2Ax%2B-0.5+%29 ALIGN=MIDDLE  ALT=\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B1%2Ax%2B-0.5+%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ></TD></TR>\n" );
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document.write( "================<BR>\n" );
document.write( "Intercepts are (x1,0) and (x2,0)<BR>\n" );
document.write( "By symmetry, the y-ints are (0,x1) and (0,x2)\r<BR>\n" );
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document.write( "</TD></TR></TABLE>\n" );