y24y2x40 write in standard form and sketch find vertexfocus
y2-4y-2x-4=0
write in standard form and sketch, find vertex,focus and directrix. show all work leading to answers.
Solution
y2-4y -2x-4=0
y2-4y+4-4-2x-4=0
(y-2)2 -2x-8=0
x=(1/2)(y-2)2-4
This is of the form
x=a(y-k)2+h
4p=2
p=1/2
Where vertex is (h,k) that is (-4,2)
focus is(h+p,k) = (-4+1/2 , 2) = (-7/2,2)
directrix, x=h-p
x= -4-1/2=-9/2
