document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1020397>Question 1020397</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Write the equation of the parabola in vertex form, with an axis of symmetry of x=4 passing through (1,-13) and (-1,-45)<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 #636280 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39620)</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=636280\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Thinking about that sketch either in the head or on paper, leading coefficient <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%3C0 ALIGN=MIDDLE  ALT=\"a%3C0\"   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=y=a%28x-4%29%5E2%2Bk ALIGN=MIDDLE  ALT=\"y=a%28x-4%29%5E2%2Bk\"   DISABLED_style= \"max-width:90%; height:auto;\" > standard form using known symmetry axis.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%28x-4%29%5E2%2Bk=y ALIGN=MIDDLE  ALT=\"a%28x-4%29%5E2%2Bk=y\"   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=a%281-4%29%5E2%2Bk=-13 ALIGN=MIDDLE  ALT=\"a%281-4%29%5E2%2Bk=-13\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=9a%2Bk=-13 ALIGN=MIDDLE  ALT=\"9a%2Bk=-13\"   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=a%28-1-4%29%5E2%2Bk=-45 ALIGN=MIDDLE  ALT=\"a%28-1-4%29%5E2%2Bk=-45\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=25a%2Bk=-45 ALIGN=MIDDLE  ALT=\"25a%2Bk=-45\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Find a and k in this system, preferably beginning with Elimination Method...<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%289a%2Bk=-13%2C25a%2Bk=-45%29 ALIGN=MIDDLE  ALT=\"system%289a%2Bk=-13%2C25a%2Bk=-45%29\"   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=9a-25a=-13-%28-45%29 ALIGN=MIDDLE  ALT=\"9a-25a=-13-%28-45%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-16a=45-13 ALIGN=MIDDLE  ALT=\"-16a=45-13\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-16a=32 ALIGN=MIDDLE  ALT=\"-16a=32\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=8a=-16 ALIGN=MIDDLE  ALT=\"8a=-16\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28a=-2%29 ALIGN=MIDDLE  ALT=\"highlight%28a=-2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Use this to find k, either equation.  Either point\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a%28x-4%29%5E2%2Bk=y ALIGN=MIDDLE  ALT=\"a%28x-4%29%5E2%2Bk=y\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=y-a%28x-4%29%5E2 ALIGN=MIDDLE  ALT=\"k=y-a%28x-4%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=-13-%28-2%29%281-4%29%5E2 ALIGN=MIDDLE  ALT=\"k=-13-%28-2%29%281-4%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=-13%2B2%28-3%29%5E2 ALIGN=MIDDLE  ALT=\"k=-13%2B2%28-3%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=-13%2B2%2A9 ALIGN=MIDDLE  ALT=\"k=-13%2B2%2A9\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=18-13 ALIGN=MIDDLE  ALT=\"k=18-13\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28k=5%29 ALIGN=MIDDLE  ALT=\"highlight%28k=5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Put everything altogether:<BR>\n" );
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