document.write( "Question 1146035: A person standing close to the edge on the top of a 160-foot building throws a baseball vertically upward. The quadratic function, s(t)= -16t^2+64t+160 models the ball’s height where s(t) is the height and t is the number of seconds after the ball is thrown.
\n" ); document.write( "(Note that s(t) is just function notation for the height of the ball and NOT s
\n" ); document.write( "multiplied by t; also note where the initial height and initial velocity values play a role in the equation.)
\n" ); document.write( "After how many seconds is the ball 100 feet above the ground’s surface? Round answer to the nearest hundredth. Don’t forget units!! \n" ); document.write( "

Algebra.Com's Answer #767307 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
There should be just one solution since the person
\n" ); document.write( "Is already 160 above ground
\n" ); document.write( " $\"+s%28t%29+=+-16t%5E2+%2B+64t+%2B+160+\"$
\n" ); document.write( " $\"+s%28t%29+=+100+\"$
\n" ); document.write( " $\"+100+=+-16t%5E2+%2B+64t+%2B+160+\"$
\n" ); document.write( " $\"+-16t%5E2+%2B+64t+%2B+60+=+0+\"$
\n" ); document.write( " $\"+-4t%5E2+%2B+16t+%2B+15+=+0+\"$
\n" ); document.write( "Use quadratic formula to solve for $\"t\"$
\n" ); document.write( "( use the positive solution ). \n" ); document.write( "

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