document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=254699>Question 254699</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A ball thrown in the air with a velocity of 24.6 m/s is at a height represented by h(t)=24.6t-4.9t^2 + 2 meters after t seconds.<BR>\n" );
document.write( "a) After how many seconds will the ball fall to the ground? (I think 2)<BR>\n" );
document.write( "b) When is the ball increasing? Decreasing?<BR>\n" );
document.write( "c) After how many seconds is the height of the ball the greatest? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #187035 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=187035\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A ball thrown in the air with a velocity of 24.6 m/s is at a height represented by h(t)=24.6t-4.9t^2 + 2 meters after t seconds.<BR>\n" );
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document.write( "Note: h(t) is the height of the ball after t seconds.<BR>\n" );
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document.write( "a) After how many seconds will the ball fall to the ground?<BR>\n" );
document.write( "The height is zero when the ball is on the ground.<BR>\n" );
document.write( "Solve -4.9t^2+24.6t+2 = 0<BR>\n" );
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document.write( "I graphed it to get:<BR>\n" );
document.write( "t = 5.10 seconds <BR>\n" );
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document.write( "b) When is the ball increasing? Decreasing?<BR>\n" );
document.write( "The vertex is at t = -b/2a = -24.6/(2(-4.9)) = 2.51 seconds<BR>\n" );
document.write( "Increasing: 0<= t <= 2.51 seconds<BR>\n" );
document.write( "Decreasing: 2.51< t < 5.10 seconds<BR>\n" );
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document.write( "c) After how many seconds is the height of the ball the greatest?<BR>\n" );
document.write( "That's what the vertex tell you: t = 2.51 seconds<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
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