document.write( "Question 277224: I would really just appreciate if someone can guide me an the formulas to use. This is credit, and we havent done this chapter. Much appreciated...\r
\n" ); document.write( "\n" ); document.write( "A miniature rocket is launched so that its height h in meters after t seconds is given by the equation h = -4.9t^2 + 19.6t + 10\r
\n" ); document.write( "\n" ); document.write( "a. draw a graph of the equation
\n" ); document.write( "b. how high is it after 3 sec?
\n" ); document.write( "c. what is the max height the rocket will attain?
\n" ); document.write( "d. How long after the launch will the rocket hit the ground?
\n" ); document.write( "

Algebra.Com's Answer #201963 by Alan3354(69443)\"\" \"About 
You can put this solution on YOUR website!
A miniature rocket is launched so that its height h in meters after t seconds is given by the equation h = -4.9t^2 + 19.6t + 10
\n" ); document.write( "a. draw a graph of the equation
\n" ); document.write( "b. how high is it after 3 sec?
\n" ); document.write( "Sub 3 for t
\n" ); document.write( "h(3) = -4.9*9 + 19.6*3 + 10
\n" ); document.write( "= 24.7 meters
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\n" ); document.write( "c. what is the max height the rocket will attain?
\n" ); document.write( "Max height is at the vertex, t = -b/2a
\n" ); document.write( "t = -19.6/2*-4.9 = 2 seconds
\n" ); document.write( "h(2) = -19.6 + 39.2 + 10
\n" ); document.write( "h(2) = 29.6 meters max height
\n" ); document.write( "-------------------------------
\n" ); document.write( "d. How long after the launch will the rocket hit the ground?
\n" ); document.write( "It impacts at h = 0
\n" ); document.write( "-4.9t^2 + 19.6t + 10
\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 \"-4.9x%5E2%2B19.6x%2B10+=+0\") has the following solutons:
\n" ); document.write( "
\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=%2819.6%29%5E2-4%2A-4.9%2A10=580.16\".
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\n" ); document.write( " Discriminant d=580.16 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-19.6%2B-sqrt%28+580.16+%29%29%2F2%5Ca\".
\n" ); document.write( "
\n" ); document.write( " \"x%5B1%5D+=+%28-%2819.6%29%2Bsqrt%28+580.16+%29%29%2F2%5C-4.9+=+-0.457807219155036\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%2819.6%29-sqrt%28+580.16+%29%29%2F2%5C-4.9+=+4.45780721915504\"
\n" ); document.write( "
\n" ); document.write( " Quadratic expression \"-4.9x%5E2%2B19.6x%2B10\" can be factored:
\n" ); document.write( " \"-4.9x%5E2%2B19.6x%2B10+=+%28x--0.457807219155036%29%2A%28x-4.45780721915504%29\"
\n" ); document.write( " Again, the answer is: -0.457807219155036, 4.45780721915504.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+-4.9%2Ax%5E2%2B19.6%2Ax%2B10+%29\"

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\n" ); document.write( "t = x
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