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# Angle-Angle-Side Similarity Theorem

In geometry, two shapes are similar if they have the same shape, but not necessarily the same size. The Angle-Angle-Side (AAS) Similarity Theorem is a way to determine if two triangles are similar. In order for two triangles to be similar by the AAS Similarity Theorem, the following must be true:

Corresponding angles are congruent. In other words, angle 1 in Triangle ABC must be equal to angle 1 in Triangle XYZ, angle 2 in Triangle ABC must be equal to angle 2 in Triangle XYZ, and so on.

The lengths of corresponding sides are proportional. What this means is that if we label the sides of Triangle ABC as follows: Side AB is side XY, Side BC is side YZ, and Side AC is side XZ. Then, we can say that AB is to XY as BC is to YZ as AC is to XZ. This proportionality relationship allows us to set up and solve proportions to find missing lengths.

The AAS Similarity Theorem provides a way for us to determine whether two triangles are similar. In order for two triangles to be considered similar by the AAS Similarity Theorem, corresponding angles must be congruent and the lengths of corresponding sides must be proportional. Once we know these things are true, we can use proportions to solve for missing lengths in similar triangles.

## FAQ

### What is the angle similarity theorem?

The angle similarity theorem states that if two angles have the same measure, then they are similar. In other words, if two angles are equal in measure, then they are equal in shape. This theorem is also known as the AAA similarity theorem.

### What is SSS SAS ASA AAS and I-AL?

SSS, SAS, ASA, and AAS are all types of similarity. SSS means "side, side, side," SAS means "side, angle, side," ASA means "angle, side, angle," and AAS means "angle, angle, side." I-AL is an acronym for "image and line." It refers to two figures that are similar because they have the same shape, but not necessarily the same size.

### What is ASA SSS AAS SAS for?

ASA, SSS, AAS, and SAS are all types of similarity. ASA means "angle, side, angle," SSS means "side, side, side," AAS means "angle, angle, side," and SAS means "side, angle, side."

### What are the 3 triangle similarity theorems?

The three triangle similarity theorems are SSS, SAS, and ASA. SSS means "side, side, side," SAS means "side, angle, side," and ASA means "angle, side, angle." These theorems state that if two triangles have corresponding sides that are in the same proportion, or corresponding angles that are equal in measure, then the triangles are similar.