Algebra.Com's Answer #627097 by ankor@dixie-net.com(22740)![\"\"](\"/images/stars/stars-13.gif\")  
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A projectile is fired at an inclination of 45 degrees to the horizontal, with a muzzle velocity of 100 feet per second.
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document.write( "The height H of the projectile is modeled by
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document.write( "Where x is the horizontal distance of the projectile from the firing point.\r
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document.write( "(A) At what horizontal distance from the firing point is the height of the
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document.write( "projectile a maximum?
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document.write( "This is quadratic equation, the max will occur at the axis of symmetry; x=-b(2a)
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document.write( "Find a: -32/100^2 = .0064, b = 1
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document.write( "x = 
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document.write( "x = +156.25 ft
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document.write( "(B) Find the maximum height of the projectile.
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document.write( "x = 156.25
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document.write( "H(x) = 78.125 ft is the max ht
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document.write( "(C) At what horizontal distance from the firing point will the projectile strike the ground?
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document.write( "It will be twice the axis of symmetry
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document.write( "x = 2(156.25)
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document.write( "x = 312.5 ft from the origin when it hits the ground
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document.write( "(D) Using a graphing utility, graph the function H,
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document.write( " 0(is equal to or less than) x (is equal to or less than) 350
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document.write( "Should look like this
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document.write( "(E) Using the graphing utility to verify the results obtained in parts B and C\r
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document.write( "(F) when the height of the projectile is 50 feet above the ground, how far has it traveled horizontally?
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document.write( "h = 50
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document.write( " = 50\r
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document.write( "Solve this with the quadratic formula; a=-.0032, b=1, c=-50
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document.write( "Two solutions
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document.write( "x = 62.5 ft on the way up
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document.write( "and
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document.write( "x = 250 ft on the way down
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document.write( "(Green line on the graph is 50')
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