document.write( "Question 812240: An object is thrown upward from the top of a 260 foot tall building with an initial velocity of 64 feet per second. The height h of the object after t seconds is given by the quadratic equation h= -16t^2+64+260. How long will it be before the object hits the ground ? \n" ); document.write( "

Algebra.Com's Answer #489076 by solver91311(24713) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "In the first place,

is NOT a quadratic equation. It is a quadratic function. There is a difference and it is important.\r
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\n" ); document.write( "\n" ); document.write( "In the second place, your quadratic function, given that it is supposed to model the height of a projectile near the surface of Earth, is incorrect. It needs to be

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\n" ); document.write( "\n" ); document.write( "Presuming that the 260 ft height of the building is measured from the ground, the ground must then be at height zero, right? So set your function equal to zero (thereby creating a quadratic equation) and solve for

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\n" ); document.write( "\n" ); document.write( "Solve for

. Discard the negative root since you don't care what went on before the object was thrown (do you?). \r
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\n" ); document.write( "\n" ); document.write( "John
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\n" ); document.write( "My calculator said it, I believe it, that settles it
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$\"The$

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