## Geometry 4.29 IM2 Writing Two-Column Proofs (SSS SAS ASA AAS HL)

But we don't have to know all three sides and all three angles SSS stands for "side, side, side" and means that we have two triangles with all three sides equal. If three sides of one triangle are equal to three sides of another triangle, the triangles are congruent.

SAS stands for "side, angle, side" and means that we have two triangles where we know two sides and the included angle are equal. If two sides and the included angle of one triangle are equal to the corresponding sides and angle of another triangle, the triangles are congruent.

ASA stands for "angle, side, angle" and means that we have two triangles where we know two angles and the included side are equal.

If two angles and the included side of one triangle are equal to the corresponding angles and side of another triangle, the triangles are congruent. AAS stands for "angle, angle, side" and means that we have two triangles where we know two angles and the non-included side are equal.

If two angles and the non-included side of one triangle are equal to the corresponding angles and side of another triangle, the triangles are congruent. HL stands for " H ypotenuse, L eg" t he longest side of a right-angled triangle is called the "hypotenuse" , the other two sides are called "legs".

See Pythagoras' Theorem to find out more. If the hypotenuse and one leg of one right-angled triangle are equal to the corresponding hypotenuse and leg of another right-angled triangle, the two triangles are congruent.

Hide Ads About Ads. Without knowing at least one side, we can't be sure if two triangles are congruent.

Two triangles are congruent if they have: exactly the same three sides and exactly the same three angles.