document.write( "Question 604841: Can you please help my in How to solve quadratic function word problems
\n" ); document.write( "my question is
\n" ); document.write( "A ball is released 6 feet above the ground and thrown vertically into the air. The equation h=-16t^+112t+6 gives the height of the ball if the initial is 112 feet per second.
\n" ); document.write( "1. Write the equation of the axis of symmetry and find the coordinates of the vertex of the graph of the equation.
\n" ); document.write( "2. What is the maximum height above the ground that the ball reaches?
\n" ); document.write( "3. How many seconds is the ball in the air?
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Algebra.Com's Answer #381456 by nerdybill(7384)\"\" \"About 
You can put this solution on YOUR website!
A ball is released 6 feet above the ground and thrown vertically into the air. The equation h=-16t^+112t+6 gives the height of the ball if the initial is 112 feet per second.
\n" ); document.write( "1. Write the equation of the axis of symmetry and find the coordinates of the vertex of the graph of the equation.
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\n" ); document.write( "axis of symmetry:
\n" ); document.write( "x = -b/(2a)
\n" ); document.write( "x = -112/(2(-16))
\n" ); document.write( "x = -112/(-32)
\n" ); document.write( "x = 3.5 (vertical line crossing at x=3.5)
\n" ); document.write( ".
\n" ); document.write( "find, y-value when x=3.5:
\n" ); document.write( "-16t^+112t+6
\n" ); document.write( "-16(3.5)^+112(3.5)+6
\n" ); document.write( "202
\n" ); document.write( "So, vertex is at (3.5, 202)
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\n" ); document.write( "2. What is the maximum height above the ground that the ball reaches?
\n" ); document.write( "202 feet
\n" ); document.write( "3. How many seconds is the ball in the air?
\n" ); document.write( "set h=0 and solve for t:
\n" ); document.write( "h=-16t^+112t+6
\n" ); document.write( "0=-16t^+112t+6
\n" ); document.write( "applying the \"quadratic formula\" gives us:
\n" ); document.write( "x {-0.1, 7.1}
\n" ); document.write( "we can throw out the negative solution (extraneous) leaving
\n" ); document.write( "x = 7.1 seconds
\n" ); document.write( ".
\n" ); document.write( "Details of quadratic formula follows:
\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 \"ax%5E2%2Bbx%2Bc=0\" (in our case \"-16x%5E2%2B112x%2B6+=+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=%28112%29%5E2-4%2A-16%2A6=12928\".
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\n" ); document.write( " Discriminant d=12928 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-112%2B-sqrt%28+12928+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%28112%29%2Bsqrt%28+12928+%29%29%2F2%5C-16+=+-0.0531676008879738\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%28112%29-sqrt%28+12928+%29%29%2F2%5C-16+=+7.05316760088797\"
\n" ); document.write( "
\n" ); document.write( " Quadratic expression \"-16x%5E2%2B112x%2B6\" can be factored:
\n" ); document.write( " \"-16x%5E2%2B112x%2B6+=+-16%28x--0.0531676008879738%29%2A%28x-7.05316760088797%29\"
\n" ); document.write( " Again, the answer is: -0.0531676008879738, 7.05316760088797.\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%2B112%2Ax%2B6+%29\"
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