document.write( "Question 438942: find the amount of time it takes if 400=-16t^2-2t+733 \n" ); document.write( "
Algebra.Com's Answer #303415 by nerdybill(7384)\"\" \"About 
You can put this solution on YOUR website!
400=-16t^2-2t+733
\n" ); document.write( "0=-16t^2-2t+733-400
\n" ); document.write( "0=-16t^2-2t+333
\n" ); document.write( "0=16t^2+2t-333
\n" ); document.write( "solve by applying the quadratic formula to get:
\n" ); document.write( "x = {4.5, -4.625}
\n" ); document.write( "we can throw out the negative answer leaving
\n" ); document.write( "x = 4.5 seconds
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\n" ); document.write( "Details of quadratic to follow:
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Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"at%5E2%2Bbt%2Bc=0\" (in our case \"16t%5E2%2B2t%2B-333+=+0\") has the following solutons:
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\n" ); document.write( " \"t%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%282%29%5E2-4%2A16%2A-333=21316\".
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\n" ); document.write( " Discriminant d=21316 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-2%2B-sqrt%28+21316+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"t%5B1%5D+=+%28-%282%29%2Bsqrt%28+21316+%29%29%2F2%5C16+=+4.5\"
\n" ); document.write( " \"t%5B2%5D+=+%28-%282%29-sqrt%28+21316+%29%29%2F2%5C16+=+-4.625\"
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\n" ); document.write( " Quadratic expression \"16t%5E2%2B2t%2B-333\" can be factored:
\n" ); document.write( " \"16t%5E2%2B2t%2B-333+=+16%28t-4.5%29%2A%28t--4.625%29\"
\n" ); document.write( " Again, the answer is: 4.5, -4.625.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+16%2Ax%5E2%2B2%2Ax%2B-333+%29\"

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