IXL | Congruent triangles: SSS, SAS, and ASA

Which rule explains why these triangles are congruent?

ASA

SSS

SAS

These triangles cannot be proven congruent.

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Which rule explains why these triangles are congruent?

SSS

SAS

ASA

These triangles cannot be proven congruent.

Two triangles are congruent if they have the same size and shape. Here are three common ways to prove that two triangles are congruent:


SSS (side-side-side) All three corresponding sides are congruent.	SAS (side-angle-side) Two sides and the angle between them are congruent.	ASA (angle-side-angle) Two angles and the side between them are congruent.

First, look for congruent sides and angles.

≅

and

∠

≅

∠

Next, write the congruency statements.

≅

Side

∠

≅

Angle

∠

Angle

The congruent sides and angles form

SA.

This is not one of the three ways to show that triangles are congruent. There is not enough information to prove that the triangles are congruent.

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