document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1013975>Question 1013975</A>: <I><SPAN STYLE=\"word-break: break-all;\"> So how would I go about solving this quadratic equation:\r<BR>\n" );
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document.write( "y=-1x^2 - 10x\r<BR>\n" );
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document.write( "I know the axis of symmetry is -5 because x=-b/2a. When I try to find the y axis however, I get y=25. Is that right? if not, how would I solve this question?  Thanks for helping me! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #630274 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39617)</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=630274\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> That is ONE equation with TWO variables, so if that is all, then nothing to \"solve\".  Your \"try to find the y axis\" makes no sense.  The y-axis is the y-axis;  the <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=25 ALIGN=MIDDLE  ALT=\"y=25\"   DISABLED_style= \"max-width:90%; height:auto;\" > is not clear.  \r<BR>\n" );
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document.write( "Best you could do is to look for x and y intercepts, and with whatever skills you know up to now, find axis of symmetry, and the vertex.\r<BR>\n" );
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document.write( "Here is what you can do.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-1%2Ax%5E2-10x=y=0 ALIGN=MIDDLE  ALT=\"-1%2Ax%5E2-10x=y=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2B10x=0 ALIGN=MIDDLE  ALT=\"x%5E2%2B10x=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%28x%2B10%29=0 ALIGN=MIDDLE  ALT=\"x%28x%2B10%29=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "meaning the x-axis intercepts are 0 and -10; which you can also call the \"roots\" of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-x%5E2-10x=0 ALIGN=MIDDLE  ALT=\"-x%5E2-10x=0\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "The form of the equation <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=kx%5E2%2Bsomething ALIGN=MIDDLE  ALT=\"y=kx%5E2%2Bsomething\"   DISABLED_style= \"max-width:90%; height:auto;\" > tells you that you have a vertical axis of symmetry; and it will occur in the exact middle between the x-axis intercepts, as YOU ALREADY FOUND, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=-5 ALIGN=MIDDLE  ALT=\"x=-5\"   DISABLED_style= \"max-width:90%; height:auto;\" > to be this symmetry axis.\r<BR>\n" );
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document.write( "The vertex happens where <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=-5 ALIGN=MIDDLE  ALT=\"x=-5\"   DISABLED_style= \"max-width:90%; height:auto;\" >, so you find the y-coordinate using <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=-x%5E2-10x ALIGN=MIDDLE  ALT=\"y=-x%5E2-10x\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-5%29%5E2-10%2A%28-5%29 ALIGN=MIDDLE  ALT=\"%28-5%29%5E2-10%2A%28-5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=25-%28-50%29 ALIGN=MIDDLE  ALT=\"25-%28-50%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=25%2B50 ALIGN=MIDDLE  ALT=\"25%2B50\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=75 ALIGN=MIDDLE  ALT=\"75\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The vertex is  (-5,75), and this is a MINIMUM, based on, again, the form of the equation you have. </SPAN>\n" );
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