+128408 13.....
y = - 16x^2 + 95x + 10
The x value that maximizes the height is given by -95/ 2(-16) = -95/-32 = 95/32
So....subbing this back into the function, we can find the max height =
-16 (95/32)^2 + 95(95/32) + 10 = 151.02 ft
It will hit the ground when
-16x^2 + 95x + 10 = 0
-95 ±√ [ 95^2 - 4(-16)(10) ]
--------------------------------------
2(-16)
-95 ±√ 9665
__________ = [ take the negative root]
-32
-95 - 98.3
__________ = 6.04 sec
-32
14.....this parabola turns upward so we can eliminate the first two answers
Using (2, 15) ....the last equation gives
4(2)^2 - 3(2) + 5
16 - 6 + 5
10 + 5 = 15
So.....the last answer is correct
