document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=284904>Question 284904</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Trying to find max y-value of the graph y=2x^2+4x+1 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #206644 by </B><A HREF=/tutors/aboutme.mpl?userid=nyc_function><B>nyc_function(2741)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nyc_function><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=nyc_function><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=206644\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The maximum y-value is the y-coordinate of the vertex.\r<BR>\n" );
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document.write( "Find the vertex in the form (x,y) and then write down the y-value.\r<BR>\n" );
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document.write( "Can you take it from here?\r<BR>\n" );
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document.write( "Do you know how to find the vertex?\r<BR>\n" );
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document.write( "You stated:\r<BR>\n" );
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document.write( "\"No, I don't understand how to find the vertex if I am not given any points for \"a\" or \"b\" (since I'm supposed to use x = -(b/2a), right?)\"\r<BR>\n" );
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document.write( "The first thing to do is find the x value using -b/2a as you said.\r<BR>\n" );
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document.write( "Let a = 2, b = 4 from your function.\r<BR>\n" );
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document.write( "x = -b/2a\r<BR>\n" );
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document.write( "x = -4/2(2)\r<BR>\n" );
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document.write( "x = -4/4\r<BR>\n" );
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document.write( "x = -1....This is the x coordinate (x-value) of the vertex.  We can now find the y-value (also called y coordinate) by replacing every x you see in your function with -1 and doing the math.\r<BR>\n" );
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document.write( "y = 2x^2+4x+1\r<BR>\n" );
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document.write( "Let x = -1\r<BR>\n" );
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document.write( "y = 2(-1)^2 + 4(-1) + 1\r<BR>\n" );
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document.write( "y = 2 - 4 + 1\r<BR>\n" );
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document.write( "y = -2 + 1\r<BR>\n" );
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document.write( "y = -1\r<BR>\n" );
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document.write( "The y-value is, in this case, the same as the x-value, which is -1.\r<BR>\n" );
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document.write( "The maximum y-value is -1.\r<BR>\n" );
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document.write( "By the way, this is a parabola that opens upward (looks like a big letter U) with vertex at the point (-1,-1).\r<BR>\n" );
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document.write( "Got it?\r<BR>\n" );
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