document.write( "Question 178252: I need help with this problem, i dont know how to set it up! thanks!
\n" ); document.write( "Suppose an object is dropped from a height ho above the ground. Then its height after t seconds is given by h = -9t 2 + ho, where h is measured in feet. Use this information to solve the problem.
\n" ); document.write( "A ball is dropped from the top of a building 54 ft tall. \r
\n" ); document.write( "\n" ); document.write( "(a) How long will it take to fall half the distance to ground level?
\n" ); document.write( "t=____ seconds \r
\n" ); document.write( "\n" ); document.write( "(b) How long will it take to fall to ground level?
\n" ); document.write( "t=___ seconds
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Algebra.Com's Answer #133242 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
(a) If the building is 54 ft tall, then 1/2 the
\n" ); document.write( "distance to the ground is \"54%2F2+=+27\"ft
\n" ); document.write( "The height after \"t\" seconds is \"27\"ft
\n" ); document.write( "\"h%5B0%5D+=+54\"ft
\n" ); document.write( "\"h+=+-9t%5E2+%2B+h%5B0%5D\"
\n" ); document.write( "\"27+=+-9t%5E2+%2B+54\"
\n" ); document.write( "\"9t%5E2+=+54+-+27\"
\n" ); document.write( "\"9t%5E2+=+27\"
\n" ); document.write( "\"t%5E2+=+3\"
\n" ); document.write( "\"t+=+sqrt%283%29\"sec
\n" ); document.write( "\"t+=+1.732\"sec
\n" ); document.write( "(b)
\n" ); document.write( "Falling to ground level,
\n" ); document.write( "\"h+=+0\"ft (the height above ground will be \"0\")
\n" ); document.write( "and, still,\"h%5B0%5D+=+54\"ft
\n" ); document.write( "\"0+=+-9t%5E2+%2B+54\"
\n" ); document.write( "\"9t%5E2+=+54\"
\n" ); document.write( "\"t%5E2+=+6\"
\n" ); document.write( "\"t+=+sqrt%286%29\"sec
\n" ); document.write( "\"t+=+2.449\"sec
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