SOLUTION: The height y (in feet) of a ball thrown by a child is given by the equation y= -1/9x^2+5x+3 , where x is the horizontal distance (in feet) from the starting point. What is the maxi

Algebra ->  Complex Numbers Imaginary Numbers Solvers and Lesson -> SOLUTION: The height y (in feet) of a ball thrown by a child is given by the equation y= -1/9x^2+5x+3 , where x is the horizontal distance (in feet) from the starting point. What is the maxi      Log On


   

Question 1034342: The height y (in feet) of a ball thrown by a child is given by the equation y= -1/9x^2+5x+3 , where x is the horizontal distance (in feet) from the starting point. What is the maximum height of the ball?
Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
The maximum height for y= -1/9x^2 + 5x + 3 occurs when x = -b/2a, that is, when
x = -5 /(-2/9) = 45/2
The maximum height itself occurs at
f(-b/2a) = f(45/2) = (-1/9)(45/2)^2 + 5(45/2) + 3 = 59.25 feet