document.write( "Question 436971: The formula h=-16t^2+vt gives the height h in feet of an object after t seconds when it is shot upward into the air with a velocity v in feet per second. After how many seconds will an object hit the ground if it is shot upward with an initial velocity of 240 feet per second?
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Algebra.Com's Answer #302328 by ankor@dixie-net.com(22740)\"\" \"About 
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The formula h=-16t^2+vt gives the height h in feet of an object after t seconds
\n" ); document.write( " when it is shot upward into the air with a velocity v in feet per second.
\n" ); document.write( " After how many seconds will an object hit the ground if it is shot upward with
\n" ); document.write( " an initial velocity of 240 feet per second?
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\n" ); document.write( "Replace h with 0 and v with 240, write the equation:
\n" ); document.write( "-16t^2 + 240t = 0
\n" ); document.write( "Simplify and change the sign, divide by -8
\n" ); document.write( "2t^2 - 30t = 0
\n" ); document.write( "Factor
\n" ); document.write( "t(2t - 30) = 0
\n" ); document.write( "Two solutions
\n" ); document.write( "t = 0 (at ground level initially)
\n" ); document.write( "and
\n" ); document.write( "2t = 30
\n" ); document.write( "t = 15 sec to hit the ground
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\n" ); document.write( "Check this in the original equation
\n" ); document.write( "-16(15^2) + 240(15) =
\n" ); document.write( "-16(225) + 3600 = 0 \n" ); document.write( "
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