document.write( "Question 936959: A ball is thrown straight upward from the ground. Its height above the ground in meters after t seconds is given by -4.9t^2+30t+c
\n" ); document.write( "1. Find the value for the constant c.
\n" ); document.write( "2. Find the values of t that make the height zero and give a practical interpretation of each value. \n" ); document.write( "

Algebra.Com's Answer #570403 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"+h%28t%29+=+-4.9t%5E2+%2B+30t+%2B+c+\"$
\n" ); document.write( "The ball is thrown from the ground, so
\n" ); document.write( "that tells me:
\n" ); document.write( " $\"+h%280%29+=+0+\"$
\n" ); document.write( " $\"+h%290%29+=+-4.9%2A0%5E2+%2B+30%2A0+%2B+c+\"$
\n" ); document.write( " $\"+0+=+0+%2B+0+%2B+c+\"$
\n" ); document.write( " $\"+c=+0+\"$
\n" ); document.write( "-------------
\n" ); document.write( " $\"+h%28t%29+=+0+\"$
\n" ); document.write( "I already know that $\"+h%280%29+=+0+\"$
\n" ); document.write( " $\"+0+=+-4.9t%5E2+%2B+30t+%2B+0+\"$
\n" ); document.write( " $\"+-4.9t%5E2+%2B+30t+=+0+\"$
\n" ); document.write( " $\"+t%2A%28+-4.9t+%2B+30+%29+=+0+\"$
\n" ); document.write( " $\"+-4.9t+%2B+30+=+0+\"$
\n" ); document.write( " $\"+4.9t+=+30+\"$
\n" ); document.write( " $\"+t+=+6.122+\"$
\n" ); document.write( "-----------------
\n" ); document.write( " $\"+t+=+0+\"$ is when ball is trown upward
\n" ); document.write( " $\"+t+=+6.122+\"$ sec is when th ball lands
\n" ); document.write( "-------------
\n" ); document.write( "Here's the plot:
\n" ); document.write( " $\"+graph%28+400%2C+400%2C+-1%2C+7%2C+-5%2C+50%2C+-4.9x%5E2+%2B+30x+%29+\"$ \r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

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