Coordinate Plane

A coordinate plane is a two-dimensional surface formed by the intersection of a horizontal line (x-axis) and a vertical line (y-axis). It is used to locate points using ordered pairs.

Ordered pairs are pairs of numbers used to represent the position of a point on a coordinate plane, written in the form (x, y).

The x-axis is the horizontal line on a coordinate plane where the y-coordinate is zero.

The y-axis is the vertical line on a coordinate plane where the x-coordinate is zero.

There are 4 quadrants in a coordinate plane.

The first quadrant is the section of the coordinate plane where both x and y coordinates are positive.

The second quadrant is the section of the coordinate plane where x coordinates are negative and y coordinates are positive.

The third quadrant is the section of the coordinate plane where both x and y coordinates are negative.

The fourth quadrant is the section of the coordinate plane where x coordinates are positive and y coordinates are negative.

To reflect a point (x, y) over the x-axis, change the sign of the y-coordinate, resulting in the point (x, -y).