# What is a Circle

## What is a Circle- How it Works - Video

### Part 1

Part 1:

The center or origin is the middle of the circle. It is equidistant from anywhere on the edge of the circle.

### Part 2

Part 2:

The radius is a line from the center of the circle to anywhere on the edge of the circle. As we can see on the right picture, we can keep adding more radii so it doesn't matter how you draw it as long as we draw it from the center to the edge.

### Part 3

Part 3:

The diameter is a line from one point on the circle to another point on the circle going through the center of the circle. As we can see on the right picture, we can keep adding more diameters so it doesn't matter how you draw it as long as we draw it from one point on the circle to another point on the circle going through the center of the circle.

### Part 4

Part 4:

Next we have a square and if all the edges next to each or the perimeter. Next we put a black line on top and roll it backwards it forms a circle. Now since circles are special shapes, we call the perimeter of a circle, the circumference.

### Example 5

Part 5:

π is the ratio of two different different distances. π is equal to the distance around the circle over the distance across the circle or the circumference over the diameter. If we curve three diameters and lay them on the circle we get approximately 3.14.... or π.

### Example 6

Part 6:

Finally, π is an irrational number, and that means is goes on forever and ever. If we use long division, it will not stop.