document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=771158>Question 771158</A>: <I><SPAN STYLE=\"word-break: break-all;\"> we're doing parabolas at the moment. I need to know how to find the turning point of a parabola, when the equation is (x-2)(x+2) for example. How do I substitute it in with the line of symmetry?? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #469974 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39618)</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=469974\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Assuming you mean, like <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=%28x-2%29%28x%2B2%29 ALIGN=MIDDLE  ALT=\"y=%28x-2%29%28x%2B2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, the \"turning point\" would be the vertex, either a maximum point or a minimum point.  Your example allows you to quickly find horizontal number line intercepts; the x value for the vertex will be in the exact middle of these horizontal  x intercepts.  \r<BR>\n" );
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document.write( "x-intercepts, the \"zeros\" of y:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28x-2%29%28x%2B2%29=0 ALIGN=MIDDLE  ALT=\"%28x-2%29%28x%2B2%29=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Either x=2 or x=-2<BR>\n" );
document.write( "THOSE are the x-intercepts, where y=0, where parabola crosses the x-axis.\r<BR>\n" );
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document.write( "What is x at the vertex?<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%282%2B%28-2%29%29%2F2=0 ALIGN=MIDDLE  ALT=\"%282%2B%28-2%29%29%2F2=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28x=0%29 ALIGN=MIDDLE  ALT=\"highlight%28x=0%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the coordinate for the vertex.\r<BR>\n" );
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document.write( "What is y coordinate at the vertex?<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=%280-2%29%280%2B2%29 ALIGN=MIDDLE  ALT=\"y=%280-2%29%280%2B2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=%28-2%29%282%29 ALIGN=MIDDLE  ALT=\"y=%28-2%29%282%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28y=-4%29 ALIGN=MIDDLE  ALT=\"highlight%28y=-4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "MEANING: the vertex of this parabola is (0, -4) </SPAN>\n" );
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