MathIsimple

Lesson 3-4: Coordinate Graphing

Master plotting points and reading coordinates using treasure map scenarios!

Learning Scenario: Treasure Map

Scenario: You found an old treasure map! The map shows a coordinate grid with clues. The treasure is hidden at point (4, 3). Can you help locate the treasure using coordinates?

What We Need to Find:

  • • Location of treasure at (4, 3)
  • • How to read coordinates
  • • How to plot points on a grid
  • • Understanding the coordinate plane

Tools We'll Use:

  • • Coordinate plane
  • • X and Y axes
  • • Ordered pairs (x, y)
  • • Plotting and reading points

Understanding the Coordinate Plane

The Coordinate Grid

A coordinate plane is like a map with two number lines that cross each other. It helps us locate points using two numbers called coordinates.

T
O

O = Origin (0,0), T = Treasure (4,3)

X-Axis (Horizontal)

The horizontal line that goes left and right

Y-Axis (Vertical)

The vertical line that goes up and down

Reading Coordinates

Ordered Pairs (x, y)

Coordinates are written as ordered pairs: (x, y). The first number tells us how far to move horizontally (left or right), and the second number tells us how far to move vertically (up or down).

(4, 3) means: Move 4 right, then 3 up

This is where our treasure is hidden!

(0, 0) is the origin - where the axes meet

Starting point for all coordinates

X-Coordinate (First Number)

Positive = move right, Negative = move left

Y-Coordinate (Second Number)

Positive = move up, Negative = move down

Plotting Points

Step-by-Step: Plot (4, 3)

Let's plot the treasure location step by step:

Step 1: Start at the origin (0, 0)

This is our starting point

Step 2: Move 4 units to the right (x = 4)

Follow the x-axis

Step 3: Move 3 units up (y = 3)

Follow the y-axis

Step 4: Mark the point - You found the treasure! 🏴‍☠️

This is point (4, 3)

Practice Problems

Problem 1: More Treasure Clues

The treasure map has more clues! Plot these points and see what shape they make:

(2, 1), (4, 1), (4, 3), (2, 3)

Plot these points in order

What shape do you see? A rectangle!

Connect the points to see the shape

Problem 2: Reading Coordinates

Look at the coordinate plane and write the coordinates for these points:

Point A: 3 units right, 2 units up

A = (3, 2)

Point B: 1 unit right, 4 units up

B = (1, 4)

Real-World Applications

Where We Use Coordinates

Maps & Navigation

  • • GPS coordinates for locations
  • • City street grids
  • • Treasure hunts and games
  • • Battleship game coordinates

Science & Technology

  • • Computer graphics and games
  • • Weather maps and charts
  • • Scientific data plotting
  • • Building blueprints

Key Takeaways

Coordinate Plane

  • Two perpendicular number lines (x and y axes)
  • Origin (0,0) is where they meet
  • Used to locate points in space
  • Like a map with a grid system

Reading & Plotting

  • Coordinates written as (x, y)
  • First number = horizontal movement
  • Second number = vertical movement
  • Always start at the origin