document.write( "Question 124223: The height h in feet of an object after t seconds is given by the function
\n" ); document.write( "h = –16t^2 + 30t + 3. How long will it take the object to hit the ground? Round your answer to the nearest thousandth. \n" ); document.write( "
Algebra.Com's Answer #91114 by ankor@dixie-net.com(22740)\"\" \"About 
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The height h in feet of an object after t seconds is given by the function
\n" ); document.write( "h = –16t^2 + 30t + 3. How long will it take the object to hit the ground? Round your answer to the nearest thousandth.
\n" ); document.write( ":
\n" ); document.write( "When it hits the ground h = 0, therefore:
\n" ); document.write( ":
\n" ); document.write( "-16t^2 + 30t + 3 = 0
\n" ); document.write( ":
\n" ); document.write( "Using the quadratic formula:
\n" ); document.write( "\"t+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( "In this problem; a=-16, b=30, c=3
\n" ); document.write( "\"t+=+%28-30+%2B-+sqrt%2830%5E2+-+4+%2A-16+%2A+3+%29%29%2F%282%2A-16%29+\"
\n" ); document.write( ":
\n" ); document.write( "\"t+=+%28-30+%2B-+sqrt%28900+-%28-192%29+%29%29%2F%28-32%29+\"
\n" ); document.write( ":
\n" ); document.write( "\"t+=+%28-30+%2B-+sqrt%28900+%2B+192+%29%29%2F%28-32%29+\"
\n" ); document.write( ":
\n" ); document.write( "\"t+=+%28-30+%2B-+sqrt%281092%29%29%2F%28-32%29+\"
\n" ); document.write( ":
\n" ); document.write( "Two solutions:
\n" ); document.write( "\"t+=+%28-30+%2B+33.0454%29%2F%28-32%29\"
\n" ); document.write( ":
\n" ); document.write( "\"t+=+%283.0454%29%2F%28-32%29\"
\n" ); document.write( ":
\n" ); document.write( "t = -.095; not a solution
\n" ); document.write( "and
\n" ); document.write( "\"t+=+%28-30+-+33.0454%29%2F%28-32%29\"
\n" ); document.write( ":
\n" ); document.write( "\"t+=+%28-63.0454%29%2F%28-32%29\"
\n" ); document.write( ":
\n" ); document.write( "t = +1.970 seconds to hit the ground
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\n" ); document.write( ":
\n" ); document.write( "You can substitute this value for t in the original equation and confirm
\n" ); document.write( "that it does, in fact, = 0, or very close to it \n" ); document.write( "
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