document.write( "Question 357150: A ball is thrown upward with an inital speed of 24.5 m/s. When is it 29.4 m high? \n" ); document.write( "
Algebra.Com's Answer #255105 by ankor@dixie-net.com(22740)\"\" \"About 
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A ball is thrown upward with an initial speed of 24.5 m/s.
\n" ); document.write( " When is it 29.4 m high?
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\n" ); document.write( "Using the formula: -4.9t^2 + 24.5t = h
\n" ); document.write( "Where
\n" ); document.write( "h = height in t seconds
\n" ); document.write( "t = time in seconds
\n" ); document.write( "4.9 = effect of gravity m/s
\n" ); document.write( "24.5 = initial upward speed m/s
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\n" ); document.write( "-4.9t^2 + 24.5t = 29.4
\n" ); document.write( ":
\n" ); document.write( "-4.9t^2 + 24.5t - 29.4 = 0
\n" ); document.write( ":
\n" ); document.write( "As luck would have it, we can divide both sides by -4.9, and have simple equation
\n" ); document.write( "t^2 - 5t + 6 = 0
\n" ); document.write( "Factors easily to:
\n" ); document.write( "(t-3)(t-2) = 0
\n" ); document.write( "Two solutions
\n" ); document.write( "t = 2 seconds, (at 29.4 m on the way up)
\n" ); document.write( "t = 3 seconds, (at 29.4 m on the way down)
\n" ); document.write( ":
\n" ); document.write( "Graphically, you can see it's approx 30ft at 2 sec and 3 sec:
\n" ); document.write( "\"+graph%28+300%2C+200%2C+-2%2C+10%2C+-10%2C+38%2C+-4.9x%5E2%2B24.5x%29+\" \n" ); document.write( "
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