document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1151571>Question 1151571</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the maximum/minimum value and the value of x when it occurs by completing the square.\r<BR>\n" );
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document.write( "a) y=5x^2-40x+81\r<BR>\n" );
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document.write( "b) y=-3x^2-30x-79 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #773367 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=773367\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 5x^2-40x+81<BR>\n" );
document.write( "divide by 5<BR>\n" );
document.write( "5(x^2-8x+81/5)<BR>\n" );
document.write( "complete the square<BR>\n" );
document.write( "5[(x-4)^2+16+(81/5-80/5)], 80/5 being 16, which has to be subtracted<BR>\n" );
document.write( "5[(x-4)^2+(1)]<BR>\n" );
document.write( "vertex is at (4, 1), and it is a minimum value of 80-160+81=1<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28300%2C300%2C-1%2C6%2C-5%2C5%2C5x%5E2-40x%2B81%29 ALIGN=MIDDLE  ALT=\"graph%28300%2C300%2C-1%2C6%2C-5%2C5%2C5x%5E2-40x%2B81%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "-3x^2-30x-79<BR>\n" );
document.write( "-3[(x^2+10x+25-(79/3))]<BR>\n" );
document.write( "-3[(x+5)^2-(4/3)]<BR>\n" );
document.write( "vertex is at (-5, -4)\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=graph%28300%2C300%2C-10%2C10%2C-10%2C10%2C-3x%5E2-30x-79%29 ALIGN=MIDDLE  ALT=\"graph%28300%2C300%2C-10%2C10%2C-10%2C10%2C-3x%5E2-30x-79%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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