Summary: Points and Lines in the Plane
Key Concepts
- We can locate, or plot, points in the Cartesian coordinate system using ordered pairs, which are defined as displacement from the x-axis and displacement from the y-axis.
- An equation can be graphed in the plane by creating a table of values and plotting points.
- Using a graphing calculator or a computer program makes graphing equations faster and more accurate. Equations usually have to be entered in the form y=_____.
- Finding the x- and y-intercepts can define the graph of a line. These are the points where the graph crosses the axes.
- The distance formula is derived from the Pythagorean Theorem and is used to find the length of a line segment.
- The midpoint formula provides a method of finding the coordinates of the midpoint dividing the sum of the x-coordinates and the sum of the y-coordinates of the endpoints by 2.