Need help with coordinates of focus pretty please! (1 Viewer)

[iamjasmina]

Hey!
Really having trouble with finding the coordinates of the focus of the parabola x^2 = 8 (y-1)

 

[NWO]

lol r u in y11 or y12?

Anways this is how u do it.

formula is : x square =4ay
Therefore, 4a=8
a=2 ( the number 2 indicates how much it moves up or down)
Vertex is : (0,1)
focus is : ( 0, -1)
Parabola is concave down with a focus of : (0, -1) and a directrix of y=3

easy 2 unit lol. ask if u have more good revision for me

 

[Smile12345]

lol r u in y11 or y12?

Anways this is how u do it.

formula is : x square =4ay
Therefore, 4a=8
a=2 ( the number 2 indicates how much it moves up or down)
Vertex is : (0,1)
focus is : ( 0, -1)
Parabola is concave down with a focus of : (0, -1) and a directrix of y=3

easy 2 unit lol. ask if u have more good revision for me

Hangon man... Why is it concave down??? I believe it's concave up... If the question had -8, it would be concave down.

Therefore the Focus is: (0,3) and the Directrix: y= -1.

(Please correct me if I'm wrong)

 

[HSC2014]

easy 2 unit lol. ask if u have more good revision for me

Not sure if trolling lol

Hangon man... Why is it concave down??? I believe it's concave up... If the question had -8, it would be concave down.

Therefore the Focus is: (0,3) and the Directrix: y= -3.

(Please correct me if I'm wrong)

Careful on the directrix

 

[Hoggy70]

directrix would be y=-1

 

[Smile12345]

Careful on the directrix

Whoops... Sorry HSC2014! Should have gone a little slower!