Algebra.Com's Answer #645083 by ankor@dixie-net.com(22740)![\"\"](\"/images/stars/stars-13.gif\")  
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A diver jumps off a diving board that is 10 ft above the water at a velocity of 12 ft/sec.
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document.write( " His height, s , in feet, above the water can be modeled by s(t) = -16t^2 + 12t + 10.
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document.write( "(a) How long is the diver in the air before he hits the water?
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document.write( "Enter the exact answer.
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document.write( "When he hits the water, s(t) = 0, therefore:
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document.write( "-16t^2 + 12t + 10 = 0
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document.write( "Simplify, divide by -2
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document.write( "8t^2 - 6t - 5 = 0
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document.write( "Factors to
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document.write( "(4t - 5)(2t + 1) = 0
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document.write( "The positive solution
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document.write( "4t = 5
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document.write( "t = 5/4
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document.write( "t = 1.25 seconds
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document.write( "The diver is in the air for _1.25_ seconds.
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document.write( ":
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document.write( "(b) What is the maximum height achieved and when does it occur?
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document.write( "Max height occurs at the axis of symmetry x = -b/(2a)
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document.write( "In this equation x=t; a=-16; b=12
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document.write( "t = 
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document.write( "t = 
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document.write( "t = .375 sec to reach max height
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document.write( "Find the max height
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document.write( "
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document.write( "s(t) = -2.25 + 4.5 + 10
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document.write( "s(t) = 12.25 ft
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document.write( "Enter the exact answers.
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document.write( "The maximum height is _12.25_ feet, and it occurs after _.375_seconds. \n" );
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