Y-axis

Definition

The y-axis is the vertical line on a coordinate plane that represents the vertical or up-and-down direction. It is used to measure and plot the position of points along the vertical dimension of the coordinate system.

5 Must Know Facts For Your Next Test

1. The y-axis is the vertical line that runs up and down on a coordinate plane, perpendicular to the horizontal x-axis.
2. The y-coordinate of a point on the coordinate plane represents its position along the vertical y-axis, with positive values above the x-axis and negative values below.
3. The y-axis is used to measure the vertical distance or height of a point on the coordinate plane, with the origin (0, 0) being the point where the x-axis and y-axis intersect.
4. When graphing linear equations, the y-axis is used to plot the dependent variable, which is the variable that changes in response to changes in the independent variable (the x-axis).
5. The y-intercept of a linear equation is the point where the graph of the equation intersects the y-axis, indicating the value of the dependent variable when the independent variable is zero.

Review Questions

• Explain the role of the y-axis in the rectangular coordinate system.
  • In the rectangular coordinate system, the y-axis represents the vertical dimension and is used to measure the position of points along the vertical direction. The y-coordinate of a point on the coordinate plane corresponds to its vertical position, with positive values above the x-axis and negative values below. The y-axis, along with the perpendicular x-axis, forms the two-dimensional coordinate plane used to plot and represent the positions of points.
• Describe how the y-axis is used when graphing linear equations.
  • When graphing linear equations, the y-axis is used to plot the dependent variable, which is the variable that changes in response to changes in the independent variable (the x-axis). The y-intercept of the linear equation, which represents the value of the dependent variable when the independent variable is zero, is the point where the graph of the equation intersects the y-axis. The slope of the line, which represents the rate of change between the dependent and independent variables, is also determined by the positions of points along the y-axis relative to the x-axis.
• Analyze the significance of the y-axis in the context of the rectangular coordinate system and graphing linear equations.
  • The y-axis is a fundamental component of the rectangular coordinate system, as it allows for the representation and measurement of the vertical or up-and-down dimension of a two-dimensional plane. In the context of graphing linear equations, the y-axis is crucial because it is used to plot the dependent variable, which changes in response to changes in the independent variable (the x-axis). The y-intercept, which represents the value of the dependent variable when the independent variable is zero, is the point where the graph of the linear equation intersects the y-axis. Additionally, the slope of the line, which indicates the rate of change between the dependent and independent variables, is determined by the positions of points along the y-axis relative to the x-axis. The y-axis, therefore, plays a vital role in both the visual representation and the mathematical analysis of linear equations within the rectangular coordinate system.

Related terms

Coordinate Plane: A two-dimensional plane that uses an x-axis and a y-axis to represent and plot the positions of points.

Ordered Pair: A pair of numbers that represents the position of a point on a coordinate plane, with the first number corresponding to the x-coordinate and the second number corresponding to the y-coordinate.

Quadrants: The four regions created by the intersection of the x-axis and y-axis on a coordinate plane, which are used to identify the location of points.