To find the coordinates of a point, you determine its position on a coordinate plane relative to two perpendicular lines called axes. These coordinates are written as an ordered pair (x, y).
A coordinate plane is formed by two number lines that intersect at a right angle at a point called the origin (0,0).
- The horizontal line is the x-axis.
- The vertical line is the y-axis.
Finding Coordinates: The Step-by-Step Process
To find the coordinates (x, y) of any point on this plane, follow these steps:
- Start at the Origin: Begin at the point where the x-axis and y-axis cross (0,0).
- Find the X-coordinate: Move horizontally (left or right) along the x-axis until you are directly above or below the point. The number on the x-axis at this position is the x-coordinate. As demonstrated in the reference, you move over to find the x-coordinate.
- Find the Y-coordinate: From your position on the x-axis, move vertically (up or down) along the y-axis until you reach the point. The number on the y-axis at this position is the y-coordinate. The reference indicates you move up to find the y-coordinate (or down if the point is below the x-axis).
- Write the Ordered Pair: Write the x-coordinate first, followed by a comma, and then the y-coordinate, enclosed in parentheses: (x, y). This is the ordered pair for the point.
Example
Based on the provided reference:
For a point labeled 'A', the process described is moving over to negative 8 and then up 5.
- The movement "over to negative 8" indicates the position on the x-axis is -8. So, the x-coordinate is -8.
- The movement "up 5" indicates the position on the y-axis is 5. So, the y-coordinate is 5.
Therefore, the coordinates or ordered pair for point A are (-8, 5). The reference explicitly states, "negative 8 is the x coordinate. And then 5 is the y coordinate."
