document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=30118>Question 30118</A>: <I><SPAN STYLE=\"word-break: break-all;\">  I am not sure on how to ask about this but on my paper for homework it says Rewrite in vertex form. and the 1st problem is      y=x^2+5x\r<BR>\n" );
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document.write( " i dont understand on how to do this could you please help me??<BR>\n" );
document.write( "Ashley  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #16932 by </B><A HREF=/tutors/aboutme.mpl?userid=Fermat><B>Fermat(136)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Fermat><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=Fermat><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=16932\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> y=x^2+5x <BR>\n" );
document.write( "This eqn (any quadratic eqn) can be written in the form,<BR>\n" );
document.write( "y = (x-a)² + b<BR>\n" );
document.write( "Quadratic eqns are parabolas, and you can think of the \"sharp end\" as the vertex.<BR>\n" );
document.write( "When you write a quadratic/parabola in the form: y = (x-a)² + b, the point (a,b) is the vertex of the parabola, and (a,b) are its coordinates.<BR>\n" );
document.write( "y = x² + 5x<BR>\n" );
document.write( "what you have to do now is complete the square.<BR>\n" );
document.write( "if  you have (x+p)², then square it, you get x² + 2px + p²<BR>\n" );
document.write( "If the coefficient of the x²-term is 1, then the coefficient of the x-term is twice the constant value, p, in the (x+p) bracket.<BR>\n" );
document.write( "So if you have x² + 5x, and the coefficent of the x-term is 5, then the coefficient of the p-term is half this, so p must be 2.5.<BR>\n" );
document.write( "Your bracketed-term must then be: (x+2.5)²<BR>\n" );
document.write( "If we expand this we get,<BR>\n" );
document.write( "x² + 5x + 6.25<BR>\n" );
document.write( "Comparing this with x² + 5x, we can see that we have 6.25 too much. So we have to subtract that.<BR>\n" );
document.write( "Here is all the action in one fell swoop,<BR>\n" );
document.write( "x² + 5x = (x+2.5)² - 6.25<BR>\n" );
document.write( "y = (x+2.5)² - 6.25<BR>\n" );
document.write( "===================<BR>\n" );
document.write( ".: a = -2.5, b = -6.25<BR>\n" );
document.write( "Vertex = (-2.5, -6.25)<BR>\n" );
document.write( "====================== </SPAN>\n" );
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