Co-ordinate Geometry

(3, 0), (-2, 0), (7, 0)

Points on the x-axis have y-coordinate equal to 0. So (3, 0), (-2, 0), and (7, 0) all lie on the x-axis.

x = 3, y = 5

For two ordered pairs to be equal, their corresponding components must be equal. So x = 3 and y = 5.

First quadrant, Fourth quadrant

First quadrant has (+, +) and fourth quadrant has (+, -), so both have positive x-coordinates.

x = 0

On the y-axis, all points have x-coordinate equal to 0, so the equation is x = 0.