But we don"t need to understand all three sides and also all 3 angles ...normally **three out of the six** is sufficient.

Tbelow are five means to find if two triangles are congruent: **SSS**, **SAS**, **ASA**, **AAS** and also **HL**.

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## 1. SSS (side, side, side)

**SSS** means "side, side, side" and also implies that we have two triangles through all 3 sides equal.

For example:

is congruent to: |

(See Solving SSS Triangles to find out more)

If three sides of one triangle are equal to 3 sides of another triangle, the triangles are congruent.

## 2. SAS (side, angle, side)

**SAS** stands for "side, angle, side" and suggests that we have two triangles wright here we understand 2 sides and also the consisted of angle are equal.

For example:

is congruent to: |

(See Solving SAS Triangles to uncover out more)

If 2 sides and also the included angle of one triangle are equal to the matching sides and also angle of another triangle, the triangles are congruent.

## 3. ASA (angle, side, angle)

**ASA** means "angle, side, angle" and also indicates that we have actually two triangles wbelow we know 2 angles and also the consisted of side are equal.

For example:

is congruent to: |

(See Solving ASA Triangles to uncover out more)

If 2 angles and also the contained side of one triangle are equal to the matching angles and side of another triangle, the triangles are congruent.

## 4. AAS (angle, angle, side)

**AAS** stands for "angle, angle, side" and also indicates that we have actually 2 triangles wright here we recognize 2 angles and the non-contained side are equal.

For example:

is congruent to: |

(See Solving AAS Triangles to discover out more)

If 2 angles and also the non-had side of one triangle are equal to the equivalent angles and side of an additional triangle, the triangles are congruent.

## 5. HL (hypotenusage, leg)

This one applies only to appropriate angled-triangles!

or |

**HL** stands for "**H**ypotenusage, **L**eg" (the longest side of a right-angled triangle is called the "hypotenuse", the other 2 sides are dubbed "legs")

It suggests we have actually two right-angled triangles with

the**exact same size of hypotenuse**and the

**exact same length for one of the various other 2 legs**.

It doesn"t matter which leg considering that the triangles might be rotated.

For example:

is congruent to: |

(See Pythagoras" Theorem to discover out more)

If the hypotenusage and also one leg of one right-angled triangle are equal to the matching hypotenusage and also leg of an additional right-angled triangle, the two triangles are congruent.

## Caution! Don"t Use "AAA"

**AAA** indicates we are provided all three angles of a triangle, but no sides.

See more: 10000*.08 - 10 Per Bag

**This is not enough information to decide if 2 triangles are congruent!**

Due to the fact that the triangles can have actually the very same angles however be **different sizes**:

is not congruent to: |

Without discovering at leastern one side, we can"t be sure if two triangles are congruent.

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