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I jus need the focus and directrix please.

I jus need the focus and directrix please.-example-1
User Nmdias
by
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1 Answer

2 votes

Answer:

the vertex is (3,-2), the focus is (3,-7/4), and the directrix is y=-9/4

Explanation:

in order to find the vertex, you convert the equation into vertex form so

y=(x-3)^2-2

With this, we can find the vertex which is at (3,-2)

In order to find the focus and diretrix, we need to find the value of p

We do this by creating the equation:

x^2=4py

in this case, (x-3)^2=4p(y+2) so 4p must equal 1 so p is 1/4

In order to find the focus, we add the value of p to the y coordinate of the vertex so the focus is (3,-2+1/4) which is (3,-7/4)

In order to find the directrix, we subtract the value of p to the y coordinate of the vertex so the directrix passes through the point (3,-2-1/4) which is (3,-9/4)

When we graph this parabola, we can tell that the directrix will be in the form of y = a and since this line passes through (3,-9/4) the directrix is y=-9/4

I hope you understand this explanation.

User Daniel Rose
by
5.2k points
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