## What are the 3 similarity theorems?

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These three theorems, known as Angle – Angle (AA), Side – Angle – Side (SAS), and Side – Side – Side (SSS), are foolproof methods for determining similarity in triangles.

## What are similarity theorems?

If two of the angles are the same, the third angle is the same and the triangles are similar. If the three sides are in the same proportions, the triangles are similar. If two sides are in the same proportions and the included angle is the same, the triangles are similar.

**What are the theorems that prove similarity?**

Theorems for proving that triangles are similar

- Similar triangles. Similar triangles are the same shape but not the same size.
- Side Side Side (SSS) If a pair of triangles have three proportional corresponding sides, then we can prove that the triangles are similar.
- Side Angle Side (SAS)

**What is AAA similarity theorem?**

Euclidean geometry may be reformulated as the AAA (angle-angle-angle) similarity theorem: two triangles have their corresponding angles equal if and only if their corresponding sides are proportional.

### How do you compare similar triangles?

If two objects have the same shape, they are called “similar.” When two figures are similar, the ratios of the lengths of their corresponding sides are equal. To determine if the triangles shown are similar, compare their corresponding sides.

### What is SSA similarity theorem?

The SAS Similarity Theorem states that if two sides in one triangle are proportional to two sides in another triangle and the included angle in both are congruent, then the two triangles are similar.

**What does SSS similarity theorem states?**

SSS Similarity Theorem: If all three pairs of corresponding sides of two triangles are proportional, then the two triangles are similar.

**When using similarity theorems angles must be?**

In similarity, angles must be of equal measure with all sides proportional. Similarity is the relation of equivalence. Two triangles A B C and D E F are similar, thus we write: △ A B C ∼ △ D E F . There are four theorems that we can use to determine if two triangles are similar.

## How do you prove SAS similarity theorem?

SAS Similarity theorem states that, “If two sides in one triangle are proportional to two sides in another triangle and the included angle in both are congruent, then the two triangles are similar”. To prove that, △PQR is similar to △XYZ. Thus, QN = YZ by SAS congruence criterion.