4/-2 flipped over the x axis

I suppose that here we have:

"(4, - 2) flipped over the x-axis"

Regardless of that, i will answer this in a kind of general way.

When we have a point (x, y) and we do a reflection over the x-axis (or the line y = 0, is the same) the reflected point will be (x, - y)

If we instead had a reflection over the y-axis (or the line x = 0) the reflected point will be (-x, y)

Then if we have the point (4, -2) and we have a reflection over the x-axis, the sign of the y-component needs to change.

Then the reflected point will be (4, -(-2)) = (4, 2)