What is SSA congruence rule?

Asked By: Badredin Antoninho | Last Updated: 4th June, 2020
Category: science space and astronomy
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The SSA. The acronym SSA (side-side-angle) refers to the criterion of congruence of two triangles: if two sides and an angle not include between them are respectively equal to two sides and an angle of the other then the two triangles are equal.

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Similarly, is there an SSA congruence?

Same as the Angle Side Side Postulate (ASS) If two triangles have two congruent sides and a congruent non included angle, then triangles are NOT NECESSARILLY congruent. This is why there is no Side Side Angle (SSA) and there is no Angle Side Side (ASS) postulate.

Subsequently, question is, what is SSS SAS ASA AAS? 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)

In this way, why does SSA congruence not work?

Four shortcuts allow students to know two triangles must be congruent: SSS, SAS, ASA, and AAS. Knowing only side-side-angle (SSA) does not work because the unknown side could be located in two different places. Because there are 6 corresponding parts 3 angles and 3 sides, you don't need to know all of them.

Why is SSA an ambiguous case?

The “Ambiguous Case” (SSA) occurs when we are given two sides and the angle opposite one of these given sides. The triangles resulting from this condition needs to be explored much more closely than the SSS, ASA, and AAS cases, for SSA may result in one triangle, two triangles, or even no triangle at all!

27 Related Question Answers Found

Is AAA a congruence theorem?

(Video) Congruent Triangles AAA
Here is a video demonstrating why AAA is NOT a valid congruence rule. As you can see in the video, triangles that have 3 pairs of congruent angles do not necessarily have the same size. AAA (Angle-Angle-Angle) is not a congruence rule!

What is congruence rule?

Side-Side-Side is a rule used to prove whether a given set of triangles are congruent. The SSS rule states that: If three sides of one triangle are equal to three sides of another triangle, then the triangles are congruent.

Is SSA a similarity theorem?

SSA theorem
Two triangles are similar if the lengths of two corresponding sides are proportional and their corresponding angles across the larger of these two are congruent.

What does it mean to be congruent?

The adjective congruent fits when two shapes are the same in shape and size. If you lay two congruent triangles on each other, they would match up exactly. Congruent comes from the Latin verb congruere "to come together, correspond with." Figuratively, the word describes something that is similar in character or type.

Is AAA a postulate?


In Euclidean geometry, the AA postulate states that two triangles are similar if they have two corresponding angles congruent. (This is sometimes referred to as the AAA Postulate—which is true in all respects, but two angles are entirely sufficient.) The postulate can be better understood by working in reverse order.

Is SAS the same as SSA?

Both of these two postulates tell you that you have two congruent sides and one congruent angle, but the difference is that in SAS, the congruent angle is the one that is formed by the two congruent sides (as you see, the "A" is between the two S), whereas with SSA, you know nothing about the angle formed by the two

How can you tell if triangles are congruent?

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

There are five ways to find if two triangles are congruent: SSS, SAS, ASA, AAS and HL.
  1. SSS (side, side, side)
  2. SAS (side, angle, side)
  3. ASA (angle, side, angle)
  4. AAS (angle, angle, side)
  5. HL (hypotenuse, leg)

Is SSA a criterion for congruence of triangle?

The SSA. The acronym SSA (side-side-angle) refers to the criterion of congruence of two triangles: if two sides and an angle not include between them are respectively equal to two sides and an angle of the other then the two triangles are equal.

How do you make a SSA triangle?

"SSA" is when we know two sides and an angle that is not the angle between the sides. use The Law of Sines first to calculate one of the other two angles; then use the three angles add to 180° to find the other angle; finally use The Law of Sines again to find the unknown side.

Is SSA a unique triangle?


You may be tempted to think that given two sides and a non-included angle is enough to prove congruence. But there are two triangles possible that have the same values, so SSA is not sufficient to prove congruence. And yet the triangles are clearly not congruent - they have a different shape and size.

How do you do similarity and congruence?

If two pairs of corresponding angles in a pair of triangles are congruent, then the triangles are similar. We know this because if two angle pairs are the same, then the third pair must also be equal. When the three angle pairs are all equal, the three pairs of sides must also be in proportion.

What are congruent triangles?

Congruent Triangles. When two triangles are congruent they will have exactly the same three sides and exactly the same three angles. The equal sides and angles may not be in the same position (if there is a turn or a flip), but they are there.

What is SAS postulate?

The Side Angle Side postulate (often abbreviated as SAS) states that if two sides and the included angle of one triangle are congruent to two sides and the included angle of another triangle, then these two triangles are congruent.

How can you tell the difference between ASA and AAS?


A.S.A. refers to an angle, then side, then an angle in anticlockwise or clockwise direction; while A.A.S. refers to an angle, then angle, then a side in anticlockwise or clockwise direction. The former means that the side and two angles related to that side.

How many congruence rules are there?

There are five ways to find if two triangles are congruent: SSS, SAS, ASA, AAS and HL.

How do you prove in SAS?

You can prove that triangles are similar using the SAS~ (Side-Angle-Side) method. SAS~ states that if two sides of one triangle are proportional to two sides of another triangle and the included angles are congruent, then the triangles are congruent.