document.write( "Question 299546: This is the exact equation she gave me: \"A child tosses a ball upward with an initial velocity of 10 f/s at a height of 3 feet. If it is not caught, how long will it be in the air?\"
\n" ); document.write( "The formula she gave us to use is h(t)=-16^2+vt+s
\n" ); document.write( "I tried setting it equal to zero but got lost after that.
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Algebra.Com's Answer #215196 by Alan3354(69443)\"\" \"About 
You can put this solution on YOUR website!
This is the exact equation she gave me: \"A child tosses a ball upward with an initial velocity of 10 f/s at a height of 3 feet. If it is not caught, how long will it be in the air?\"
\n" ); document.write( "The formula she gave us to use is h(t)=-16^2+vt+s
\n" ); document.write( "I tried setting it equal to zero but got lost after that.
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\n" ); document.write( "If you set it to zero, you can find the time when it hits the ground, when h=0. That's how long it is in the air.
\n" ); document.write( "h(t)=-16^2+vt+s
\n" ); document.write( "Actually, it's h(t)=-16t^2+vt+s
\n" ); document.write( "h(t) = -16t^2 + 10t + 3
\n" ); document.write( "-16t^2 + 10t + 3 = 0
\n" ); document.write( "\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"-16x%5E2%2B10x%2B3+=+0\") has the following solutons:
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\n" ); document.write( " \"x%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=%2810%29%5E2-4%2A-16%2A3=292\".
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\n" ); document.write( " Discriminant d=292 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-10%2B-sqrt%28+292+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%2810%29%2Bsqrt%28+292+%29%29%2F2%5C-16+=+-0.221500234082346\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%2810%29-sqrt%28+292+%29%29%2F2%5C-16+=+0.846500234082346\"
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\n" ); document.write( " Quadratic expression \"-16x%5E2%2B10x%2B3\" can be factored:
\n" ); document.write( " \"-16x%5E2%2B10x%2B3+=+%28x--0.221500234082346%29%2A%28x-0.846500234082346%29\"
\n" ); document.write( " Again, the answer is: -0.221500234082346, 0.846500234082346.\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%2B10%2Ax%2B3+%29\"

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\n" ); document.write( "Ignore the negative number.
\n" ); document.write( "t =~0.8465 seconds to impact
\n" ); document.write( "You were doing it right, setting it to zero.\r
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