Math - Grade 8

Understanding the Coordinate Plane

The coordinate plane is a flat surface used to locate points. It is made up of two number lines: the x-axis (horizontal) and the y-axis (vertical). These axes meet at a point called the origin, which has coordinates (0, 0). The plane is divided into four quadrants. In Quadrant I, both x and y are positive. In Quadrant II, x is negative and y is positive. In Quadrant III, both are negative. In Quadrant IV, x is positive and y is negative. Points are written as ordered pairs (x, y). The x-coordinate tells how far to move left or right, while the y-coordinate tells how far to move up or down. Points on the axes follow special rules: if a point is on the x-axis, its y-value is 0; if it is on the y-axis, its x-value is 0.