document.write( "Question 316805: h= -16t2 +80t + 50
\n" ); document.write( "Use this position polynomial to calculate the following: \r
\n" ); document.write( "\n" ); document.write( "1.The height of the object after 2 seconds
\n" ); document.write( "2.The height of the object after 5 seconds
\n" ); document.write( "3.The maximum height of the object
\n" ); document.write( "4.How long the the object will take to reach the ground?
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Algebra.Com's Answer #226797 by nerdybill(7384)\"\" \"About 
You can put this solution on YOUR website!
h= -16t2 +80t + 50
\n" ); document.write( "Use this position polynomial to calculate the following:
\n" ); document.write( "1.The height of the object after 2 seconds
\n" ); document.write( "h= -16(2)^2 +80(2) + 50
\n" ); document.write( "h= -16(4) +160 + 50
\n" ); document.write( "h= -64 +160 + 50
\n" ); document.write( "h = 146
\n" ); document.write( "2.The height of the object after 5 seconds
\n" ); document.write( "h= -16(5)^2 +80(5) + 50
\n" ); document.write( "h= -16(25) +400 + 50
\n" ); document.write( "h= 50
\n" ); document.write( "3.The maximum height of the object
\n" ); document.write( "axis of symmetry:
\n" ); document.write( "t = -b/(2a) = -80/(-32) = 2.5
\n" ); document.write( "h= -16(2.5)^2 +80(2.5) + 50
\n" ); document.write( "h = 150
\n" ); document.write( "4.How long the the object will take to reach the ground?
\n" ); document.write( "set h to zero solve for t
\n" ); document.write( "0= -16t2 +80t + 50
\n" ); document.write( "Apply the quadratic formula to get:
\n" ); document.write( "t = {-0.562, 5.562}
\n" ); document.write( "Toss out the negative solution leaving:
\n" ); document.write( "t = 5.562
\n" ); document.write( "Details of quadratic to follow:
\n" ); document.write( "\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"at%5E2%2Bbt%2Bc=0\" (in our case \"-16t%5E2%2B80t%2B50+=+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=%2880%29%5E2-4%2A-16%2A50=9600\".
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\n" ); document.write( " Discriminant d=9600 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-80%2B-sqrt%28+9600+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"t%5B1%5D+=+%28-%2880%29%2Bsqrt%28+9600+%29%29%2F2%5C-16+=+-0.561862178478973\"
\n" ); document.write( " \"t%5B2%5D+=+%28-%2880%29-sqrt%28+9600+%29%29%2F2%5C-16+=+5.56186217847897\"
\n" ); document.write( "
\n" ); document.write( " Quadratic expression \"-16t%5E2%2B80t%2B50\" can be factored:
\n" ); document.write( " \"-16t%5E2%2B80t%2B50+=+-16%28t--0.561862178478973%29%2A%28t-5.56186217847897%29\"
\n" ); document.write( " Again, the answer is: -0.561862178478973, 5.56186217847897.\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%2B80%2Ax%2B50+%29\"

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