document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=297765>Question 297765</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The vertex of this parabola is at (4, -3). When the x-value is 5, the <BR>\n" );
document.write( "y-value is -6. What is the coefficient of the squared expression in the parabola's equation?\r<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 #214381 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=214381\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The vertex of this parabola is at (4, -3). When the x-value is 5, the <BR>\n" );
document.write( "y-value is -6. What is the coefficient of the squared expression in the parabola's equation? <BR>\n" );
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document.write( "y = ax^2 + bx + c<BR>\n" );
document.write( "Find a,b,c<BR>\n" );
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document.write( "From the vertex info: 4 = -b/(2a)<BR>\n" );
document.write( "b = -8a<BR>\n" );
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document.write( "So y = ax^2 (-8a)x + c<BR>\n" );
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document.write( "From the (5,-6) and the (4,-3) info:<BR>\n" );
document.write( "-6 = a(25) -8a(5) +c<BR>\n" );
document.write( "-3 = a(16) -8a(4) +c<BR>\n" );
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document.write( "Rearrange the two equations and solve for a and for c.<BR>\n" );
document.write( "Since b = -8a you also will know b.<BR>\n" );
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document.write( "Now you know a,b, and c so you can write the <BR>\n" );
document.write( "equation of the parabola.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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