Chapter 3: Coordinate Geometry

Chapter 3 Summary

Quick Reference Card

The Basics

TermDefinition
Cartesian planePlane with x and y axes
Origin(0,0)(0, 0) - where axes meet
Abscissax-coordinate
Ordinatey-coordinate

The Four Quadrants

QuadrantSignsLocation
I(+,+)(+, +)Top-right
II(−,+)(-, +)Top-left
III(−,−)(-, -)Bottom-left
IV(+,−)(+, -)Bottom-right

Special Points

LocationCoordinates
On x-axis(a,0)(a, 0)
On y-axis(0,b)(0, b)
Origin(0,0)(0, 0)

Key Facts

  1. Order matters! (3,4)≠(4,3)(3, 4) \neq (4, 3)

  2. Every point has unique coordinates

  3. Every coordinate pair represents a unique point

  4. Distance from origin = x2+y2\sqrt{x^2 + y^2} (Pythagoras!)

🎉 Chapter 3 Complete!

Visualizer
Coordinate Plane
XYOA(3, 4)B(-2, 3)C(-3, -2)D(4, -1)Q I (+,+)Q II (-,+)Q III (-,-)Q IV (+,-)
Point A: (3, 4)
Quadrant I

Interactive Visualization