document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1187078>Question 1187078</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a ball tossed upward from the ground its height in feet above the ground after second is given by the quadratic function y =-3x²+42x. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #818016 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=818016\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> the equation is y =-3x²+42x.\r<BR>\n" );
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document.write( "here's what it looks like on a graph.\r<BR>\n" );
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document.write( "to solve manually, do the following.\r<BR>\n" );
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document.write( "put the equation in standard quadratic form.\r<BR>\n" );
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document.write( "that is ax^2 + bx + c = 0\r<BR>\n" );
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document.write( "a is the coefficient of the x^2 term = -3.<BR>\n" );
document.write( "b is the coefficient of the x term = 42.<BR>\n" );
document.write( "c is the constant term = 0 (if it's not there, it's equal to 0).\r<BR>\n" );
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document.write( "the maximum / minimum value on the graph is at x = -b/(2a).<BR>\n" );
document.write( "that makes x equal to -42 / -6 = 7.\r<BR>\n" );
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document.write( "that's the value of the x-coordinate.\r<BR>\n" );
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document.write( "the value of the y-coordinate is the value you get when you replace x in the equation with 7.\r<BR>\n" );
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document.write( "y = -3x^2 + 42x becomes y = -3*7^2 + 42*7 = -147 + 294 = 147.\r<BR>\n" );
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document.write( "that's the same value you see on the graph.\r<BR>\n" );
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document.write( "your solution is that the maximum height is 147 feet.\r<BR>\n" );
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document.write( "the number of seconds it takes to get there is the value of x from x = 0 to x = 7 which is 7 seconds.\r<BR>\n" );
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document.write( "here's a reference on quadratic equations you might find helpful.\r<BR>\n" );
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document.write( "<a  rel=nofollow HREF= \"https://www.mathsisfun.com/algebra/quadratic-equation.html\" target = \"_blank\">https://www.mathsisfun.com/algebra/quadratic-equation.html</a>\r<BR>\n" );
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document.write( " </SPAN>\n" );
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