How do you describe the location of something on a flat surface, or map?
You use coordinates.
Coordinates are an address within a coordinate plane like (1, 3).
Here's one:
Tip: plane just means flat surface in math.
At the center of every coordinate plane is the address (0, 0). It's called the origin.
There are two lines intersecting, or crossing each other, right at the origin.
The horizontal line is called the x-axis.
Horizontal means from left to right. ↔️
The vertical line is called the y-axis.
Vertical means from top to bottom. ↕️
The point where the x-axis and y-axis meet is called the origin.
Any point in a coordinate plane can be written with two numbers like (3, 5).
The first number is always the x-coordinate.
It describes how far to the right of the origin a point is. ➡
The second number is the y-coordinate.
It tells how far up from the origin a point is. ⬆
Coordinates like (x, y) are called ordered pairs because the first number is always the x-axis value.
Always write coordinates with the x and y values inside parenthesis and separated by a comma.
Tip: The x-coordinate is always written before the y-coordinate.
The origin is always at (0, 0).
All other coordinates describe how far away they are from the origin. 🛣️
Look at the orange dot below.
What are its coordinates?
First, we find its location along the x-axis.
Start at the origin and move to the right along the x-axis.
Stop when you're right under the dot. 🚦
We see that we've traveled 4 units to the right of the origin.
We write it as our x-coordinate, the first number in the ordered pair.
(4, ___)
Now, we look at where the point is along the y-axis.
We see that we've gone up 3 units from the origin.
We write that as the y-coordinate in the ordered pair.
(4, 3)
The ordered pair is complete! We now know the coordinates of the orange dot. 👏
Pretend you hear about a treasure at this coordinate:
(5,7)
Can you graph its location on a coordinate plane?
Where do you start?
Yes. You always start at the origin because this is where the x-axis and y-axis meet.
First, move 5 units to the right.
Why 5?
Because the x-coordinate in (5, 7) is 5.
How many units do we move up?
Very good! 7 units up.
Now we mark the point where we stopped.
This is point (5,7). ✅
Excellent.
It's possible to move from one point to another in a coordinate plane.
Let's say you start at (2,1). If you move right 6 units, where do you end?
First, find the starting point. That's point (2,1).
Now, move right 6 units.
Where do you end up?
That's right! At point (8,1). ✅
Start at (6,2), then move up 3 units.
Where do you end up?
First, graph the starting point at (6,2).
Then, move up 3 units.
Where did you end up?
You got it. At point (6,5). ✅
Awesome.
Let's try another example.
You start at point (3,5). You move right 4 units, then move up 3 units. Where do you end up?
Let's graph our starting point.
We move right 4 units.
Now, we move 3 units up from this point.
At what point did we end up?
Perfect. At point (7,8). ✅
You did a great job learning about coordinates and the coordinate plane.
Now, practice your new skills.