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The focus of the parabola -40x = y 2 is: (-10, 0) (10, 0) (0, 10) (0, -10)

1 Answer

7 votes

Answer:

(-10, 0)

Explanation:

The parabola opens to the left, and its vertex is at (0, 0). The focus must have an x-coordinate that is negative. The only viable choice is ...

(-10, 0)

__

The equation is in the form ...

4px = y^2

where p is the distance from the vertex to the focus.

In the given equation, 4p = -40, so p=-10, and the focus is 10 units to the left of the vertex. In this equation, the vertex corresponds to the values of the variables where the squared term is zero: (x, y) = (0, 0).

The focus of the parabola -40x = y 2 is: (-10, 0) (10, 0) (0, 10) (0, -10)-example-1
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