Overview
This lecture introduces the basics of coordinate planes, covering important terms, concepts, and how to plot points.
Coordinate Plane Basics
- The coordinate plane is a flat, two-dimensional surface used to plot points, lines, and curves.
- It consists of two axes: the x-axis (horizontal) and the y-axis (vertical).
Axes and Origin
- The x-axis runs left to right (horizontal), and the y-axis runs up and down (vertical).
- The origin is the center point where the x-axis and y-axis intersect, located at (0, 0).
Ordered Pairs and Plotting Points
- Points are given as ordered pairs (x, y), where x is the horizontal value and y is the vertical value.
- To plot (3, 5): start at the origin, move right 3 units (x), then up 5 units (y).
- To plot (6, -7): start at the origin, move right 6 units, then down 7 units.
- To plot (-7, 9): start at the origin, move left 7 units, then up 9 units.
- Always move along the x-axis first, then the y-axis.
Quadrants
- The coordinate plane is divided into four quadrants:
- Quadrant I: top right (e.g., point (3, 5))
- Quadrant II: top left (e.g., point (-7, 9))
- Quadrant III: bottom left
- Quadrant IV: bottom right (e.g., point (6, -7))
- Quadrants are numbered from I to IV, moving counterclockwise.
Key Terms & Definitions
- Coordinate Plane — a two-dimensional surface for plotting points.
- X-axis — the horizontal axis on the coordinate plane.
- Y-axis — the vertical axis on the coordinate plane.
- Origin — the intersection point of the x and y axes, (0, 0).
- Ordered Pair — a pair of numbers (x, y) specifying a point’s location.
- Quadrant — one of the four sections of the coordinate plane.
Action Items / Next Steps
- Review the vocabulary terms and practice plotting points on a coordinate plane.