document.write( "Question 1088880: H(t)= -5t^2 + at + b
\n" ); document.write( "At time t=0, a ball was thrown upward from the top of a building. Before the ball hit the ground, its height h(t), in feet, at the time t seconds is given by the function above. A and b are constants. If the ball reached its maximum height of 125 feet at time t=3, what could be the height of the building? \n" ); document.write( "

Algebra.Com's Answer #703250 by ikleyn(52776) $\"\"$ $\"About$

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\n" ); document.write( "H(t)= -5t^2 + at + b
\n" ); document.write( "At time t=0, a ball was thrown upward from the top of a building. Before the ball hit the ground, its height h(t), in feet,
\n" ); document.write( "at the time t seconds is given by the function above. A and b are constants.
\n" ); document.write( "If the ball reached its maximum height of 125 feet at time t=3, what could be the height of the building?
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\n" ); document.write( "\n" ); document.write( "Before starting my solution, I must make this notice.\r
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document.write( "    The form of your equation (the coefficient -5 at t^2) means that the units are (should be/must be) METERS, not feet.\r\n" );
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document.write( "    So, I will solve it assuming that the input is in METERS.\r\n" );
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document.write( "The fact that \"the ball reached its maximum height of 125 feet at time t=3\" means that the vertex form of the quadratic function H(t) is\r\n" );
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document.write( "H(t) = .\r\n" );
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document.write( "It means that H(t) =  =  = . \r\n" );
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document.write( "In turn, it means that the height of the building is 80 meters.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Answer. The height of the building is 80 meters.\r
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