document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=695141>Question 695141</A>: <I><SPAN STYLE=\"word-break: break-all;\"> When a ball is kicked in the air, its height in meter above the ground can be modeled by h(t)= -4.9t^2 + 14.7t and the distance it travels can be modeled by d(t)=16t where t is the time in seconds.<BR>\n" );
document.write( "a. How long is the ball in the air<BR>\n" );
document.write( "b. How far does it travel before it hits the ground<BR>\n" );
document.write( "c. What is the maximum height of the ball<BR>\n" );
document.write( "Can you please help?<BR>\n" );
document.write( "Thank you! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #428332 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=428332\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> When a ball is kicked in the air, its height in meter above the ground can be modeled by h(t)= -4.9t^2 + 14.7t and the distance it travels can be modeled by d(t)=16t where t is the time in seconds.<BR>\n" );
document.write( "a. How long is the ball in the air<BR>\n" );
document.write( "The ball starts on the ground and ends up on the ground.<BR>\n" );
document.write( "It's height on the ground is zero.<BR>\n" );
document.write( "Solve: -4.9t^2+14.7t = 0<BR>\n" );
document.write( "t(-4.9t+14.7) = 0<BR>\n" );
document.write( "t = 0 and t = 14.7/4.9 = 3 seconds<BR>\n" );
document.write( "Ans: The ball in in the air for 3 seconds<BR>\n" );
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document.write( "b. How far does it travel before it hits the ground<BR>\n" );
document.write( "Ans: 3 meters<BR>\n" );
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document.write( "c. What is the maximum height of the ball<BR>\n" );
document.write( "Vertex occurs at t = -b/(2a) = -14.7/(2*-4.9) = 3/2<BR>\n" );
document.write( "h(3/2) = -4.9(3/2)^2 + 14.7(3/2) = 11.025 meters (maximum height)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );