document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1169870>Question 1169870</A>: <I><SPAN STYLE=\"word-break: break-all;\"> From the top of the building, a ball is thrown straight up with an initial velocity of 128 feet per second. The equation <BR>\n" );
document.write( "s = −16t2 + 128t + 144<BR>\n" );
document.write( " gives the height s of the ball t seconds after it is thrown. Find the maximum height (in feet) reached by the ball and the time (in seconds) it takes for the ball to hit the ground. (Hint: Let s = 0 and solve for t.)<BR>\n" );
document.write( "144 ft<BR>\n" );
document.write( "A rectangular building is 144 ft tall.<BR>\n" );
document.write( "A curved path starts at the top-right side of the building and goes up and to the right past the right edge of the building. The path gets less steep as it reaches a high point, and then it goes down and to the right, getting steeper as it goes.<BR>\n" );
document.write( "The ball is at the end of the path midway between the top of the building and the ground, and its height above the ground is labeled s.<BR>\n" );
document.write( "A vertical dashed line starts at the ball and goes down to touch the ground.<BR>\n" );
document.write( "1.The maximum height reached by the ball is ? Feet ?<BR>\n" );
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document.write( "2. The ball hits the ground after 9<BR>\n" );
document.write( " seconds.                       I did figure out number 2 i just need help with the first one </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #794708 by </B><A HREF=/tutors/aboutme.mpl?userid=Solver92311><B>Solver92311(821)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Solver92311><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=Solver92311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=794708\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font face=\"Times New Roman\" size=\"+2\">\r<BR>\n" );
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document.write( "You need the time value when the function value is maximum.  Since the function is a quadratic with a negative lead coefficient, the graph is a concave down parabola making the vertex of the parabola the point where the value of the function is a maximum.\r<BR>\n" );
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document.write( "For any parabola modeled by an equation of the form <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large y\ =\ ax^2\,+\,bx\,+\,c\">, the value of the independent variable (<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large t\"> for your situation) is found by calculating <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \frac{-b}{2a}\">.\r<BR>\n" );
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document.write( "Once you know the value of <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large t_{max}\">, then calculate the value of <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large s\(t_{max}\)\">\r<BR>\n" );
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document.write( "John<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE e^{i\pi}\ +\ 1\ =\ 0\"><BR>\n" );
document.write( "My calculator said it, I believe it, that settles it<BR>\n" );
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document.write( "From <https://www.algebra.com/cgi-bin/upload-illustration.mpl> <BR>\n" );
document.write( "I > Ø<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \ \\r\"> </SPAN>\n" );
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