document.write( "Question 1146083: 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( "How many seconds will it take for the ball to return to the surface? Round answer to the nearest hundredth. Don’t forget units!! \n" ); document.write( "

Algebra.Com's Answer #767357 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "To answer your question, solve the equation  s(t) = 160  \r\n" );
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document.write( "(I mean that the surface is the top of the 160-feet building --  it is how I interpret the term \"return\").\r\n" );
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document.write( "This equation is\r\n" );
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document.write( "     = 160,\r\n" );
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document.write( "or simplified\r\n" );
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document.write( "     = 0.\r\n" );
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document.write( "The root you want is  t =  = 4 seconds.    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "These words \"close to the edge\" were introduced into the problem formulation with the only goal to confuse the reader.\r
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\n" ); document.write( "\n" ); document.write( "It is \"pure US american\" style formulating Math problems (to load them with excessive and unnecessary words).\r
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\n" ); document.write( "\n" ); document.write( "In normal mathematical formulation, a professional and knowledgeable author never uses such tricks.\r
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\n" ); document.write( "\n" ); document.write( "My advise to the author is to remove these words from the text.\r
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