What is an Angle?
An angle is two rays that share the same endpoint, the point where they intersect is called the vertex. The two rays are called the sides of the angle.

Here are some angles:

There are many types of angles:

Acute Angles are cute and small:

Obtuse Angles are big and of course obese:

A right angle is an angle measuring 90 degrees. It is two lines or line segments that meet at a right angle and are to be perpendicular:

Complementary angles are two angles that sum up to 90 degrees:

Supplementary angles are two angles that sum up to 180 degrees:

Measuring Angles

To measure an angle, we must use a device called a protractor, a protractor uses units called degrees. Measuring an angle is really easy!

Vertical Angles are two lines that meet,vertical angles have the same degree for each side.

For example, a few vertical angles are listed below:

Now that we have learned about vertical angles, we must learn about what they make. When they cross over, of course they make an angle, but what are these called? Well, some vertical angles make right angles, any right angle that a vertical angle forms is called a perpendicular line.

We have learned our second session, next, we will learn about shapes and figures. Enjoy!