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Which signs do x- and y-coordinates have in each quadrant?

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Diagram showing a double cone intersected by planes at different angles, producing the conic sections: a horizontal plane creates a circle, a tilted plane creates an ellipse, a plane parallel to the cone's side forms a parabola, and a steep plane produces a hyperbola. Each section is labeled, with the axis and apex of the cone indicated. — analytic geometry The conic sections result from intersecting a plane with a double cone, as shown in the figure. There are three distinct families of conic sections: the ellipse (including the circle), the parabola (with one branch), and the hyperbola (with two branches).

In analytic geometry, the Cartesian plane is divided into four quadrants by the intersection of the x- and y-axes. The signs of the coordinates $(x, y)$ in each quadrant are as follows:

Quadrant I: Both x and y are positive $(+, +)$ .
Quadrant II: x is negative and y is positive $(-, +)$ .
Quadrant III: Both x and y are negative $(-, -)$ .
Quadrant IV: x is positive and y is negative $(+, -)$ .1