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# Supplementary Angles: All You Need to Know

Geometry can be tricky for some students, but understanding supplementary angles is a key concept that can help make other topics in the subject easier to understand. Supplementary angles are two angles whose measurements add up to 180 degrees. Let’s explore this concept further.

## Defining Supplementary Angles

Supplementary angles are two angles whose measurements add up to 180 degrees. For example, if one angle measures 90 degrees, then the other angle must measure 90 degrees as well in order for them to be considered supplementary. Together, they form a straight line. It’s important to note that while the two supplementary angles do have the same measurement, they are still considered different angles and have different vertexes (the point where two rays meet).

## Using Supplementary Angles

Knowing how supplementary angles work is important when solving certain geometry problems. For instance, when given only one angle in a problem, you can use your knowledge of supplementary angles to find out what the other missing angle is by subtracting it from 180 degrees. This can be especially useful if you are trying to solve for an unknown triangle or a quadrilateral (a four-sided polygon). In addition, you can use your knowledge of supplementary angles to determine whether or not an object is perpendicular (90 degrees) or oblique (not 90 degrees). By determining which type of object you are dealing with and what kind of angle it has, you will be better equipped to find the measurements of all its sides and corners.

## Conclusion:

Supplementary angles are an essential concept when it comes to understanding geometry concepts such as triangles and quadrilaterals. Knowing how supplementary angles work can help students more easily solve complex geometry problems by providing them with the necessary information needed to fill in the gaps within their equations. With practice and patience, students will soon become comfortable using supplemental angles within their geometry studies!

## FAQ

### What are supplementary angles in geometry?

Supplementary angles are two angles whose measurements add up to 180 degrees. For example, if one angle measures 90 degrees, then the other angle must measure 90 degrees as well for them to be considered supplementary.

### Why is it called supplementary angle?

Supplementary angles are so named because they form a straight line when combined, thus supplementing each other. When two supplementary angles are put together, it forms a full rotation of 180 degrees.

### What are examples of supplementary angles?

Examples of supplementary angles include an angle that measures 45 degrees and another angle that measures 135 degrees, or an angle measuring 30 degrees and an angle measuring 150 degrees.