document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=99654>Question 99654</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Determine the equation of the axis of symmetry for the parabola whose x - intercepts are (-3, 0) and (1,0). </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #72520 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=72520\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The axis of symmetry is always the point right in the middle of the two intercepts. That is why it is called the axis of symmetry.\r<BR>\n" );
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document.write( "So if we have x-intercepts of -3 and 1, just average them to get the axis of symmetry:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-3%2B1%29%2F2=-2%2F2=-1 ALIGN=MIDDLE  ALT=\"%28-3%2B1%29%2F2=-2%2F2=-1\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "So the axis of symmetry is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=-1 ALIGN=MIDDLE  ALT=\"x=-1\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Notice if we graph a parabola with x-intercepts (-3, 0) and (1,0) we get\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=drawing%28500%2C+500%2C+-10%2C+10%2C+-10%2C+10%2C+%0D%0Agraph%28+500%2C+500%2C+-10%2C+10%2C+-10%2C+10%2C+%28x%2B3%29%28x-1%29%29%2C%0D%0Aline%28-1%2C20%2C-1%2C-20%29%0D%0A%29+ ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" > graph of the parabola with x-intercepts (-3, 0) and (1,0) with the axis of symmetry <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=-1 ALIGN=MIDDLE  ALT=\"x=-1\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Notice the vertical line at <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=-1 ALIGN=MIDDLE  ALT=\"x=-1\"   DISABLED_style= \"max-width:90%; height:auto;\" > evenly splits the parabola in two </SPAN>\n" );
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