If i is a zero, -i is also a zero.
The way you get a complex zero is by taking the square root of a negative number. Taking the sqrt (-1) = + and - i
The maximum height is yo<span> = 0</span>
When the projectile is at its maximum height <span> v</span>y = 0.
Note that the maximum height is determined solely by the initial velocity in the y direction and the acceleration due to gravity. :)
My reasonable estimate might be about 2 1/2 feet. I know that because taking three rulers up to your bedroom or a normal room and get about 2 or 2 1/2 feet
Change the function into vertex form:
f(x)=x²-10x+16
make a square by (adding half of -10)², which is 25, then subtract it:
f(x)=x²-10x+25-25+16
f(x)=(x-5)²-9
so the vertex is at (5,-9)
another way to do it:
f(x)=x²-10x+16
the vertex is when x=-

, b=-10, a=1 in this case.
x=-(-10/2*1)=5
plug x=5 into the quadratic function, you get f(x)=-9
First do 8 divided by 9 = 0.88 x 6 x 19 start from the left and work to the right 0.88 x 6 = 5.33 x 19 = 101.3