document.write( "Question 697309: A ball is thrown vertically upward. After t seconds, its height h (in feet) is given by the function . \r
\n" ); document.write( "\n" ); document.write( "h(t)=100t-16t^2\r
\n" ); document.write( "\n" ); document.write( "What is the maximum height that the ball will reach? Height= ? feet\r
\n" ); document.write( "\n" ); document.write( "Do not round your answer.
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Algebra.Com's Answer #429862 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
Plot this function with \"+h%28t%29+\" on the vertical axis
\n" ); document.write( "and \"+t+\" on the horizontal axis.
\n" ); document.write( "This is a parabola that has a maximum. The maximum is
\n" ); document.write( "half-way between the 2 roots. One of the roots is at
\n" ); document.write( "(0,0) at the instant the ball was thrown upward.
\n" ); document.write( "Find the other root by setting \"+h%28t%29+=+0+\" , and
\n" ); document.write( "find the time when the ball comes back to the ground.
\n" ); document.write( "\"+100t+-+16t%5E2+=+0+\"
\n" ); document.write( "\"+50t+-+8t%5E2+=+0+\"
\n" ); document.write( "\"+t%2A%28+50+-+8t+%29+=+0+\"
\n" ); document.write( "\"+50+-+8t+=+0+\"
\n" ); document.write( "\"+8t+=+50+\"
\n" ); document.write( "\"+t+=+25%2F4+\"
\n" ); document.write( "The time half-way between \"+0+\" and \"+25%2F4+\"
\n" ); document.write( "is \"+25%2F8+\". Now find the height at \"+t+=+25%2F8+\"
\n" ); document.write( "\"+h%28t%29+=+100t+-+16t%5E2+\"
\n" ); document.write( "\"+h%2825%2F8%29+=+100%2A%2825%2F8%29+-+16%2A%2825%2F8%29%5E2+\"
\n" ); document.write( "\"+h%2825%2F8%29+=+12.5%2A25+-+16%2A%28625%2F64%29+\"
\n" ); document.write( "\"+h%2825%2F8%29+=+312.5+-+625%2F4+\"
\n" ); document.write( "\"+h%2825%2F8%29+=+312.5+-+156.25+\"
\n" ); document.write( "\"+h%2825%2F8%29+=+156.25+\"
\n" ); document.write( "The maximum height is 156.25 ft
\n" ); document.write( "Here's the plot:
\n" ); document.write( "\"+graph%28+400%2C+400%2C+-2%2C+8%2C+-20%2C+200%2C+-16x%5E2+%2B+100x+%29+\"\r
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