Plotting Points on the Cartesian Plane

Learn step-by-step how to plot points using coordinates on the Cartesian plane with simple student-friendly notes.

1. Understanding How to Plot a Point

Every point on the Cartesian plane is written as an ordered pair \((x, y)\). Plotting a point means marking its exact position based on these values.

To place the point correctly, we always move horizontally first (x-direction) and then vertically (y-direction).

1.1. Definition

Plotting a point means locating its position by moving x units left/right from the origin and then y units up/down.

2. Step-by-Step Method to Plot a Point

To plot a point \((x, y)\), follow these steps carefully:

2.1. Step 1: Start at the Origin

The origin is \((0,0)\). All movements begin from here.

2.2. Step 2: Move Along the x-axis

Look at the value of x:

  • If x is positive → move right
  • If x is negative → move left

2.3. Step 3: Move Parallel to the y-axis

After reaching the point on the x-axis, move vertically:

  • If y is positive → move up
  • If y is negative → move down

2.4. Step 4: Mark the Final Point

Where the horizontal and vertical movements meet, mark the point and label it.

2.4.1. Example

Plot \((4, -3)\):

  • From origin, move 4 units right
  • Then move 3 units down
  • Mark the point in Quadrant IV

3. Understanding the Direction of Movement

Signs of the coordinates decide the direction in which we move:

3.1. Direction Rules

  • +x → right
  • -x → left
  • +y → up
  • -y → down

3.2. Quick Visual Summary

For \((x, y)\):

  • Right & Up → Quadrant I
  • Left & Up → Quadrant II
  • Left & Down → Quadrant III
  • Right & Down → Quadrant IV

4. Examples of Plotting Points

These examples help in understanding how the sign of each coordinate affects the final position.

4.1. Example 1

Plot \((2, 3)\):

  • 2 units right
  • 3 units up
  • Point lies in Quadrant I

4.2. Example 2

Plot \((-4, 2)\):

  • 4 units left
  • 2 units up
  • Point lies in Quadrant II

4.3. Example 3

Plot \((-3, -1)\):

  • 3 units left
  • 1 unit down
  • Point lies in Quadrant III

4.4. Example 4

Plot \((5, -4)\):

  • 5 units right
  • 4 units down
  • Point lies in Quadrant IV

4.5. Axis Examples

  • \((0, 6)\) → on y-axis
  • \((7, 0)\) → on x-axis