document.write( "Question 967989: An object is thrown upward from the top of a 96 foot building with an initial velocity of 80 feet per second. The height h of the object after t seconds is given by the quadratic equation h = -16t^2+80t+96. When will the object hit the ground? \n" ); document.write( "

Algebra.Com's Answer #591623 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
There is only 1 time when the object is on the ground,
\n" ); document.write( "and that is when $\"+h+=+0+\"$
\n" ); document.write( " $\"+h+=++-16t%5E2+%2B+80t+%2B+96+\"$
\n" ); document.write( " $\"+0+=++-16t%5E2+%2B+80t+%2B+96+\"$
\n" ); document.write( "Divide through by $\"+16+\"$
\n" ); document.write( " $\"++-t%5E2+%2B+5t+%2B+6+\"$
\n" ); document.write( " $\"+%28+-t+%2B+6+%29%2A%28+t+%2B+1+%29+=+0+\"$
\n" ); document.write( " $\"+t+=+6+\"$ ( time must be positive so, $\"+t+\"$ can't be $\"+-1+\"$ )
\n" ); document.write( "------------------
\n" ); document.write( "the object will hit the ground in 6 sec
\n" ); document.write( "Here's the plot:
\n" ); document.write( " $\"+graph%28+400%2C+400%2C+-2%2C+7%2C+-50%2C+200%2C+-16x%5E2+%2B+80x+%2B+96+%29+\"$ \r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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