document.write( "Question 195718: A baseball player has hit a ball. The height, y, of the ball x seconds after it is hit is given by y= -16x^2 + 80x + 3.
\n" ); document.write( "At what time will the ball reach its maximum height? I used the quadratic formula and my answer was 2.04
\n" ); document.write( "What is the maximum height of the ball? I used the original formula.My answer was 232.78
\n" ); document.write( "When will the ball hit the ground? My answer was 4.08\r
\n" ); document.write( "\n" ); document.write( "Is this right??
\n" ); document.write( "thanks \n" ); document.write( "
Algebra.Com's Answer #146755 by Alan3354(69443)\"\" \"About 
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A baseball player has hit a ball. The height, y, of the ball x seconds after it is hit is given by y= -16x^2 + 80x + 3.
\n" ); document.write( "At what time will the ball reach its maximum height? I used the quadratic formula and my answer was 2.04
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\n" ); document.write( "Find the apogee, which is the vertex of the parabola:
\n" ); document.write( "hmax = -b/2a
\n" ); document.write( "= -80/(-32) = 2.5 seconds
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\n" ); document.write( "What is the maximum height of the ball? I used the original formula.My answer was 232.78
\n" ); document.write( "It's at time = 2.5 seconds.
\n" ); document.write( "y = -16*2.5^2 + 80*2.5 + 3
\n" ); document.write( "ymax = 103 feet
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\n" ); document.write( "When will the ball hit the ground? My answer was 4.08
\n" ); document.write( "Set y = 0
\n" ); document.write( "-16x^2 + 80x + 3 = 0
\n" ); document.write( "x = 2.5 + (sqrt(103))/4 seconds
\n" ); document.write( "x = ~ 5.037222891 seconds
\n" ); document.write( "It's not 5 seconds even, because the ball started up from 3' elevation.\r
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