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You can put this solution on YOUR website!
The coefficient of t^2 is gravity so it is negative. (Upward force is positive)
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\n" ); document.write( "If an object is propelled upward from a height of s feet at an initial velocity of v feet per second, then its height h after t seconds is given by the equation h=-16t^2+vt+s, where h is in feet.
\n" ); document.write( " If the object is propelled from a height of 4 feet with an initial velocity of 96 feet per second, its height is given by the equation h=-16t^2+96t+4.
\n" ); document.write( "After how many seconds is the height 112 feet?
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\n" ); document.write( "-16t^2 + 96t + 4 = 112
\n" ); document.write( "-16t^2 + 96t + 4 - 112 = 0
\n" ); document.write( "-16t^2 + 96t - 108 = 0
\n" ); document.write( "Simplify, divide eq by 4
\n" ); document.write( "-4t^2 + 24t - 27 = 0
\n" ); document.write( " use the quadratic formula, a=-4; b=24; c=-27,
\n" ); document.write( " I obtained two valid solutions
\n" ); document.write( "t = 1.5 sec, at 112 ft on the way up
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\n" ); document.write( "t = 4.5 sec, on the way down
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\n" ); document.write( "Looks like this graphically, green line is 112 ft
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