document.write( "Question 878388: From the top of a building, a rock is thrown straight up with an initial velocity of 32 ft. per second. The equation s = -16t^2 + 32t + 48 gives the height (s) of the rock (t) seconds after its thrown. Find the maximum height reached by the rock. \n" ); document.write( "

Algebra.Com's Answer #529920 by solver91311(24713) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "Your height function is a quadratic of the form

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\n" ); document.write( "\n" ); document.write( "Since your function has a negative lead coefficient, the graph is a parabola that opens downward. Therefore the vertex of the parabola is at the maximum value of the function.\r
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\n" ); document.write( "\n" ); document.write( "The

value of the vertex of

is given by

and the value of the function at the vertex is the function evaluated at this

value. In other words, the vertex is at the point

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\n" ); document.write( "\n" ); document.write( "You need the value of

that gives the independent variable value of the vertex for

which is given by

and then you need to evaluate your height function at that value of

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\n" ); document.write( "\n" ); document.write( "John
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\n" ); document.write( "My calculator said it, I believe it, that settles it
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$\"The$

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