document.write( "Question 1165980: A ball is thrown upward with an initial velocity of 30 feet per second from a point that is 24 feet above the ground. The height (h) in feet of the ball at time t (in second) is given by the equation: h(t)= -16t^2+30t+24
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Algebra.Com's Answer #790448 by ikleyn(52792) $\"\"$ $\"About$

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document.write( "The function h(t) = -16t^2 + 30t + 24  is a quadratic function, whose plot is a parabola opened down.\r\n" );
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document.write( "This quadratic function has the maximum at the value of its argument  t = , \r\n" );
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document.write( "where \"a\" is the coefficient at t^2  and \"b\" is the coefficient at t.\r\n" );
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document.write( "    In your case, a= -16,  b= 30, so the function gets the maximum at  t =  = 0.9375.\r\n" );
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document.write( "So, the ball gets the maximum height  0.9375 seconds after is hit straight up. \r\n" );
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document.write( "The maximum height then is  h(0.9375) = -16*0.9375^2 + 30*0.9375 + 24 = 38.0625 ft.\r\n" );
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\n" ); document.write( "\n" ); document.write( "On finding the maximum/minimum of a quadratic function, see the lessons \r
\n" ); document.write( "\n" ); document.write( "    - HOW TO complete the square to find the minimum/maximum of a quadratic function\r
\n" ); document.write( "\n" ); document.write( "    - Briefly on finding the minimum/maximum of a quadratic function\r
\n" ); document.write( "\n" ); document.write( "    - HOW TO complete the square to find the vertex of a parabola\r
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\n" ); document.write( "\n" ); document.write( "On solving similar problems to yours in this post, see the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Problem on a projectile moving vertically up and down\r
\n" ); document.write( "\n" ); document.write( "    - Problem on an arrow shot vertically upward\r
\n" ); document.write( "\n" ); document.write( "    - Problem on a ball thrown vertically up from the top of a tower \r
\n" ); document.write( "\n" ); document.write( "    - Problem on a toy rocket launched vertically up from a tall platform\r
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