+817 23)
y=x^2 -8x +18
y -18 = x^2-8x
y-18 +16 = (x-8x+16)
y-2 = (x-4)^2
vertex(4,2)
Because (x-4)^2 has a coefficient of 1, and (y-k)= 1/4p(x-h)^2, p's value is 1/4.
Because x has a positive coefficient, the parabola is pointing upwards, so the focus is above the vertex.
Focus(4, 2.25)
Directrix( y = 1.75)
24).
(x-2)^2 + (y-1)^2 = 16
becomes
(x-2+4)^2 + (y+1-6)^2 = 16
cleaned up
(x+2)^2 + (y-5)^2 = 16
