document.write( "Question 188763This question is from textbook An Applied Approach
\n" ); document.write( ": An object is thrown downward, with an initial speed of 16ft/s, from the top of a building 480 ft. high. How many seconds later will the object hit the ground? Use the equation d = vt + 16t2 , where d is the distance in feet, v is the initial speed, and t is the time in seconds. \n" ); document.write( "
Algebra.Com's Answer #141579 by stanbon(75887)\"\" \"About 
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An object is thrown downward, with an initial speed of 16ft/s, from the top of a building 480 ft. high. How many seconds later will the object hit the ground? Use the equation d = vt + 16t2 , where d is the distance in feet, v is the initial speed, and t is the time in seconds.
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\n" ); document.write( "d(t) = vt + 16t^2
\n" ); document.write( "16t + 16t^2 = 480
\n" ); document.write( "t + t^2 = 3
\n" ); document.write( "t^2 + t -3 = 0
\n" ); document.write( "t = [-1 +- sqrt(1-4*-3)]/2\r
\n" ); document.write( "\n" ); document.write( "t = [-1 +- sqrt(13)]/2
\n" ); document.write( "Positive solution:\r
\n" ); document.write( "\n" ); document.write( "t = [2.6056]/2
\n" ); document.write( "t = 1.3028 seconds
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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