document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=115642>Question 115642</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Algebra 1 chapter 9 Resource Book lesson 9.3 Practice A\r<BR>\n" );
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document.write( "I am having dificulty trying to figure out the coordinates to a problem that contains an a, b, c and even more when b and c are sometimes missing.\r<BR>\n" );
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document.write( "Find the coordinates of the vertex.\r<BR>\n" );
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document.write( "1. y= 3x²\r<BR>\n" );
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document.write( "2. y= 5x²-1\r<BR>\n" );
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document.write( "3. y= x²+6x<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 #84171 by </B><A HREF=/tutors/aboutme.mpl?userid=vertciel><B>vertciel(183)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=vertciel><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=84171\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Hello there,\r<BR>\n" );
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document.write( "When b and c are missing, their value is 0 because they're missing!\r<BR>\n" );
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document.write( "1. The vertex is at (0,0). \r<BR>\n" );
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document.write( "There are two ways to find this out:\r<BR>\n" );
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document.write( "1) For the graph y = x^2, the vertex is at (0,0). The equation y = 3x^2 means that y = x^2 is stretched out, so the vertex hasn't changed.\r<BR>\n" );
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document.write( "2) You can use the formula <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+h+=+-b%2F2a.+ ALIGN=MIDDLE  ALT=\"+h+=+-b%2F2a.+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "h = -b/2a\r<BR>\n" );
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document.write( "  = 0/2(3)\r<BR>\n" );
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document.write( "  = 0\r<BR>\n" );
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document.write( "Plug 0 into the equation of the parabola:   \r<BR>\n" );
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document.write( "l = f(0) = 0^2\r<BR>\n" );
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document.write( "         = 0\r<BR>\n" );
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document.write( "2. y = 5x^2 - 1\r<BR>\n" );
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document.write( "h = -b/2a\r<BR>\n" );
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document.write( "  = -0/2(5)\r<BR>\n" );
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document.write( "  = 0\r<BR>\n" );
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document.write( "k = f(0) = 5(0)^2 - 1\r<BR>\n" );
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document.write( "         = -1\r<BR>\n" );
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document.write( "Therefore, the vertex is at (0, -1). \r<BR>\n" );
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document.write( "Try to do #3 on your own. Please write back if you need more help! </SPAN>\n" );
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