SOLUTION: y2-8y+12x-8=0 what is the focus , directrix and the endpoints of latus rectum

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Question 1092269: y2-8y+12x-8=0 what is the focus , directrix and the endpoints of latus rectum
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
y%5E2-8y%2B12x-8=0
y%5E2-8y=-12x%2B8
"16" will complete-the-square.
y%5E2-8y%2B16=-12x%2B8%2B16
%28y-4%29%5E2=-12x%2B24
highlight_green%28-12%28x-2%29=%28y-4%29%5E2%29

VERTEX (2,4)
FOCUS (-1,4)
DIRECTRIX x=5
EndPoints of LATUS RECTUM (-1,-2) and (-1,10)




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-12(-1-2)=(y-4)^2
36=(y-4)^2
y-4=0+- 6
y=4+- 6
y=-2 or y=10