What is a

# Y-axis

A **y-axis **is the vertical axis on the Cartesian coordinate plane. The y-axis starts at negative infinity and increases to positive infinity. The y-axis is also the starting, or 0 point, for measuring how far a point extends horizontally on a graph. In experiments, the dependent variable is placed along the y-axis, which is otherwise known as the “effect” that is produced by the “cause” of the independent variable—placed on the x-axis.

A **y-axis **is the line on a graph that is drawn from bottom to top. This axis is parallel to which coordinates are measured. The numbers placed on the y-axis are called y-coordinates. Ordered pairs are written in parentheses, with the x-coordinate written first, followed by the y-coordinate: (x, y).