Coordinate Plane: Definitions and Examples

Coordinate Plane: Definitions, Formulas, & Examples

GET TUTORING NEAR ME!

(800) 434-2582

By submitting the following form, you agree to Club Z!'s Terms of Use and Privacy Policy

    Introduction:

    The coordinate plane is a fundamental concept in mathematics that allows us to graph and analyze two-dimensional shapes and functions. It is also known as the Cartesian plane, named after the French mathematician René Descartes, who introduced the concept in the 17th century.

    The coordinate plane consists of two perpendicular number lines, the x-axis and y-axis, that intersect at the origin (0,0). The x-axis is the horizontal line, and the y-axis is the vertical line. Each point in the plane is defined by an ordered pair of coordinates (x, y), where x is the horizontal coordinate, and y is the vertical coordinate.

    To visualize the coordinate plane, we can imagine a flat surface, like a sheet of paper, divided into four quadrants. The first quadrant is the upper right corner, where both x and y coordinates are positive. The second quadrant is the upper left corner, where x coordinates are negative, and y coordinates are positive. The third quadrant is the lower left corner, where both x and y coordinates are negative. The fourth quadrant is the lower right corner, where x coordinates are positive, and y coordinates are negative.

    Graphing points in the coordinate plane is simple. To graph the point (3,4), for example, we move three units to the right along the x-axis and four units up along the y-axis. The point where the two lines intersect is the point (3,4). Similarly, the point (-2,-5) is located two units to the left along the x-axis and five units down along the y-axis.

    The coordinate plane is useful for graphing geometric figures and functions. For example, to graph a line, we only need two points. Suppose we want to graph the line that passes through the points (1,2) and (3,4). We start by plotting the two points and drawing a line connecting them. The slope of the line is the change in y divided by the change in x. In this case, the slope is (4-2)/(3-1) = 2/2 = 1. This means that for every unit we move to the right along the x-axis, we move one unit up along the y-axis. We can use this information to plot more points on the line or to find the equation of the line using point-slope form or slope-intercept form.

    Another important concept in the coordinate plane is distance. The distance between two points (x1, y1) and (x2, y2) can be found using the distance formula: d = sqrt((x2 – x1)^2 + (y2 – y1)^2). For example, the distance between the points (1,2) and (4,6) is d = sqrt((4 – 1)^2 + (6 – 2)^2) = sqrt(9 + 16) = sqrt(25) = 5.

    The coordinate plane is also used in advanced mathematics to graph and analyze more complex functions, such as conic sections, polar coordinates, and parametric equations. Conic sections are curves that result from slicing a cone at different angles. They include circles, ellipses, parabolas, and hyperbolas, and can be graphed in the coordinate plane using their general equations.

    Polar coordinates are another way of specifying points in the plane. Instead of using (x, y) coordinates, polar coordinates use (r, ?) coordinates, where r is the distance from the origin to the point, and ? is the angle formed between the positive x-axis and the line connecting the point to the origin. Polar coordinates are useful for graphing curves that have radial symmetry, such as spirals and polar graphs.

    Definition:

    A coordinate plane is a flat surface that is divided into two perpendicular number lines, usually labeled the x-axis and the y-axis. These axes intersect at a point known as the origin, which is denoted by the coordinates (0,0). The x-axis is horizontal and runs from left to right, while the y-axis is vertical and runs from bottom to top. Each point in the plane is assigned a unique set of coordinates, consisting of an x-coordinate and a y-coordinate, which indicate its position relative to the origin.

    Examples:

    1. Plotting points: The most basic use of a coordinate plane is to plot points. To plot a point, we simply locate its coordinates on the plane and mark it with a dot. For example, the point (2,3) represents a point that is 2 units to the right of the origin and 3 units up from the origin. We can also plot negative coordinates, such as (-2,-3), which represents a point that is 2 units to the left of the origin and 3 units down from the origin.
    2. Graphing lines: The coordinate plane can also be used to graph lines. To graph a line, we simply plot two or more points on the plane and then draw a line through them. For example, the line y = 2x + 1 can be graphed by plotting the points (0,1) and (1,3) and then drawing a line through them.
    3. Finding distances: The distance between two points on a coordinate plane can be calculated using the distance formula: d = sqrt((x2-x1)^2 + (y2-y1)^2). For example, the distance between the points (1,2) and (4,6) can be calculated as d = sqrt((4-1)^2 + (6-2)^2) = sqrt(9+16) = sqrt(25) = 5.
    4. Solving equations: The coordinate plane can also be used to solve equations. For example, the equation y = x^2 can be solved by graphing the function on the plane and finding the x-intercepts (where the graph crosses the x-axis). In this case, the x-intercepts occur at (0,0) and (1,0), so the solutions to the equation are x = 0 and x = 1.
    5. Quadrants: The coordinate plane is divided into four quadrants, numbered I, II, III, and IV, as shown below:
      css
    II | I

    1. III| IV

    Quadrant I is the upper right quadrant, where both the x-coordinate and y-coordinate are positive. Quadrant II is the upper left quadrant, where the x-coordinate is negative and the y-coordinate is positive. Quadrant III is the lower left quadrant, where both the x-coordinate and y-coordinate are negative. Quadrant IV is the lower right quadrant, where the x-coordinate is positive and the y-coordinate is negative. The quadrants are often used to describe the location of points on the plane, as well as the direction and orientation of lines and angles.

    Conclusion:

    In conclusion, the coordinate plane is an essential tool in mathematics and other fields that require the representation of data in a two-dimensional space. It provides a visual representation of ordered pairs, allowing for the plotting of points, the determination of slopes and intercepts, and the analysis of geometric shapes and figures. Understanding how to read and interpret the coordinate plane is critical in fields such as physics, engineering, and computer science, where it is used to model and solve complex problems. Therefore, a solid understanding of the coordinate plane is an important foundation for success in these areas and many others.

    Quiz

    What are the two axes in the coordinate plane called?

    • Answer: The x-axis and the y-axis.

    What is the origin of the coordinate plane?

    • Answer: The point where the x-axis and the y-axis intersect, which is usually labeled as (0,0).

    Which quadrant is located in the upper-right portion of the coordinate plane?

    • Answer: The first quadrant.

    What are the coordinates of a point located on the x-axis?

    • Answer: The y-coordinate of a point on the x-axis is always 0.

    What are the coordinates of a point located on the y-axis?

    • Answer: The x-coordinate of a point on the y-axis is always 0.

    Which quadrant is located in the lower-left portion of the coordinate plane?

    • Answer: The third quadrant.

    What is the distance formula for finding the distance between two points on the coordinate plane?

    • Answer: d = ?((x2 – x1)² + (y2 – y1)²)

    Which quadrant is located in the upper-left portion of the coordinate plane?

    • Answer: The second quadrant.

    What is the slope-intercept form of a linear equation on the coordinate plane?

    • Answer: y = mx + b, where m is the slope and b is the y-intercept.

    What is the equation for a vertical line on the coordinate plane?

    • Answer: x = a, where a is the x-coordinate of any point on the line.

    If you’re interested in online or in-person tutoring on this subject, please contact us and we would be happy to assist!


    Coordinate Plane:

    Result

    (data not available)

    Visual representation

    
(drawn with normal vector (5, -4, 3))

    Equation forms

    z = -(a x)/c - (b y)/c + d/c

    a x + b y + c z - d = 0

    Find the right fit or it’s free.

    We guarantee you’ll find the right tutor, or we’ll cover the first hour of your lesson.