document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1189918>Question 1189918</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The graph of a certain quadratic y = ax^2 + bx + c is a parabola with vertex (-4,0) which passes through the point (1,-75). What is the value of a? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #821424 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20849)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=821424\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "The graph of a certain quadratic <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+ax%5E2+%2B+bx+%2B+c+ ALIGN=MIDDLE  ALT=\"y+=+ax%5E2+%2B+bx+%2B+c+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "in vertex form\"<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+%28ax%5E2+%2B+bx%29+%2B+c+ ALIGN=MIDDLE  ALT=\"y+=+%28ax%5E2+%2B+bx%29+%2B+c+\"   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%5E2+%2B+%28b%2Fa%29x%2B%28b%2F%282a%29%29%5E2%29+-a%28b%2F%282a%29%29%5E2%2B+c+ ALIGN=MIDDLE  ALT=\"y+=+a%28x%5E2+%2B+%28b%2Fa%29x%2B%28b%2F%282a%29%29%5E2%29+-a%28b%2F%282a%29%29%5E2%2B+c+\"   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%5E2+%2B+%28b%2Fa%29x%2B%28b%2F%282a%29%29%5E2%29+-b%5E2%2F4a%2B+c+ ALIGN=MIDDLE  ALT=\"y+=+a%28x%5E2+%2B+%28b%2Fa%29x%2B%28b%2F%282a%29%29%5E2%29+-b%5E2%2F4a%2B+c+\"   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+-+b%2F%282a%29%29%5E2+-b%5E2%2F4a%2B+c+ ALIGN=MIDDLE  ALT=\"y=+a%28x+-+b%2F%282a%29%29%5E2+-b%5E2%2F4a%2B+c+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( " a parabola with vertex (<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-4 ALIGN=MIDDLE  ALT=\"-4\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0 ALIGN=MIDDLE  ALT=\"0\"   DISABLED_style= \"max-width:90%; height:auto;\" >) =><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h=-4 ALIGN=MIDDLE  ALT=\"h=-4\"   DISABLED_style= \"max-width:90%; height:auto;\" >-><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h=b%2F%282a%29 ALIGN=MIDDLE  ALT=\"h=b%2F%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >=><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b%2F%282a%29=-4 ALIGN=MIDDLE  ALT=\"b%2F%282a%29=-4\"   DISABLED_style= \"max-width:90%; height:auto;\" >-><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b=-8a ALIGN=MIDDLE  ALT=\"b=-8a\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+k=0 ALIGN=MIDDLE  ALT=\"+k=0\"   DISABLED_style= \"max-width:90%; height:auto;\" >-><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0=-b%5E2%2F%284a%29%2B+c+ ALIGN=MIDDLE  ALT=\"0=-b%5E2%2F%284a%29%2B+c+\"   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=c=b%5E2%2F4a+ ALIGN=MIDDLE  ALT=\"c=b%5E2%2F4a+\"   DISABLED_style= \"max-width:90%; height:auto;\" >-><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=c=%28-8a%29%5E2%2F%284a%29 ALIGN=MIDDLE  ALT=\"c=%28-8a%29%5E2%2F%284a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >-><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=c=64a%5E2%2F%284a%29 ALIGN=MIDDLE  ALT=\"c=64a%5E2%2F%284a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >-><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=c=16a ALIGN=MIDDLE  ALT=\"c=16a\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=+a%28x+%2B4%29%5E2+-%28-8a%29%5E2%2F%284a%29%2B+16a ALIGN=MIDDLE  ALT=\"y=+a%28x+%2B4%29%5E2+-%28-8a%29%5E2%2F%284a%29%2B+16a\"   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+%2B4%29%5E2+-16a%2B+16a ALIGN=MIDDLE  ALT=\"y=+a%28x+%2B4%29%5E2+-16a%2B+16a\"   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+%2B4%29%5E2++ ALIGN=MIDDLE  ALT=\"y=+a%28x+%2B4%29%5E2++\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "which passes through the point (<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1 ALIGN=MIDDLE  ALT=\"1\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-75 ALIGN=MIDDLE  ALT=\"-75\"   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=-75=+a%281+%2B4%29%5E2 ALIGN=MIDDLE  ALT=\"-75=+a%281+%2B4%29%5E2\"   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=-75=+25a ALIGN=MIDDLE  ALT=\"-75=+25a\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a=-3 ALIGN=MIDDLE  ALT=\"a=-3\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "then your equation is:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=-3%28x+%2B4%29%5E2 ALIGN=MIDDLE  ALT=\"y=-3%28x+%2B4%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=-3x%5E2+-+24x+-+48 ALIGN=MIDDLE  ALT=\"y=-3x%5E2+-+24x+-+48\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
document.write( "<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+drawing%28+600%2C+600%2C+-10%2C+10%2C+-80%2C+10%2C+%0D%0Acircle%281%2C-75%2C.13%29%2Clocate%281%2C-75%2Cp%281%2C-75%29%29%2C%0D%0Acircle%28-4%2C0%2C.13%29%2Clocate%28-4%2C0%2CV%28-4%2C0%29%29%2C%0D%0Agraph%28+600%2C+600%2C+-10%2C+10%2C+-80%2C+10%2C+-3x%5E2+-+24x+-+48%29%29+ ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );