Diameter: A line segment that passes through the center and has its endpoints on the circle.
Radius: A line segment that starts at the center and stops at the endpoint of the circle.
Let's remember the difference between finding the area of the circle
(what is inside) and the circumference of the circle
(the distance around the circle).
The value of π is approximately 3.14

Let's look at the circle properties: 

The area of the sector follows the same formula than the area but you have to find the central angle and divide it by 360. You are just getting a piece of the area.

The arc of the circle is the same formula as the circumference but you have to divide the central angle by 360.

Let's say you have a circle with a center of (-3,5)

and a radius of 6 units. Let's graph the circle and find its standard and general form. 

Let's say you have a

circle with

a center of (-3,5)

and a radius of 6 units. 

When two parallel lines are crossed by another line
(called the transversal).
You need to remember which angles are equal to each other.

Let's Practice

Let's Practice

Let's Practice

More Tutorials

A triangle is a closed figure with 3 sides.
The sum of the interior angles of any triangle is 180 degrees.

There are three different types of triangles depending on the sides and angles.
Let's see the different types of triangles and their properties:

Any triangle with a 90°-degree angle is a right triangle.
The measurement of the sides of a right triangle can be calculated with the following formula:

where C is the hypotenuse, A and B are the legs of the triangle

Let's see the different types of triangles and their properties:

The right triangle 45-45-90 follows the ratio 

X:X:X√2
Let's do an example: 

The right triangle 30:60:90 follows the ratio 

X:X√3:2X
Let's do an example: