`25x^2+y^2=25`

`x^2+(y^2)/25=1`

So `b = 1` and `a = 5`. In this example, the major axis is vertical.

So the vertices are at `(0, -5)` and `(0, 5)`.

To find *c*, we proceed as before:

`c=sqrt(a^2-b^2)`

`=sqrt(25-1)`

`=sqrt24`

`=4.899`

So the foci are at `(0, -4.9)` and `(0, 4.9)`.

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