exactly the very same three sides and specifically the very same three angles.

But we don"t need to know all 3 sides and also all 3 angles ...usually three out of the six is enough.

There are five ways to uncover if 2 triangles room congruent: SSS, SAS, ASA, AAS and HL.

You are watching: What other information do you need in order to prove the triangles congruent using the sas

1. SSS (side, side, side)

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SSS stands for "side, side, side" and way that we have two triangles through all three sides equal.

For example:

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is congruent to:
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(See addressing SSS triangles to find out more)


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


2. SAS (side, angle, side)

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SAS means "side, angle, side" and method that we have two triangles whereby we recognize two sides and also the consisted of angle room equal.

For example:

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is congruent to:
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(See resolving SAS triangles to discover out more)


If two sides and also the contained angle that one triangle space equal come the corresponding sides and also angle of an additional triangle, the triangles space congruent.


3. ASA (angle, side, angle)

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ASA represents "angle, side, angle" and way that we have actually two triangles wherein we recognize two angles and also the consisted of side room equal.

For example:

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is congruent to:
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(See addressing ASA triangles to find out more)


If 2 angles and also the contained side the one triangle space equal to the corresponding angles and also side of an additional triangle, the triangles are congruent.


4. AAS (angle, angle, side)

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AAS stands for "angle, angle, side" and method that we have two triangles wherein we understand two angles and the non-included side space equal.

For example:

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is congruent to:
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(See solving AAS triangle to discover out more)


If 2 angles and the non-included next of one triangle space equal come the equivalent angles and also side of another triangle, the triangles are congruent.


5. HL (hypotenuse, leg)

This one applies only to best angled-triangles!

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or
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HL means "Hypotenuse, Leg" (the longest next of a right-angled triangle is called the "hypotenuse", the other two political parties are called "legs")

It way we have actually two right-angled triangle with

the same size of hypotenuse and also the same length for one of the other two legs.

It doesn"t issue which leg since the triangles can be rotated.

For example:

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is congruent to:
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(See Pythagoras" to organize to find out more)


If the hypotenuse and one leg of one right-angled triangle space equal to the equivalent hypotenuse and leg of another right-angled triangle, the two triangles are congruent.


Caution! Don"t use "AAA"

AAA way we are offered all three angles of a triangle, yet no sides.

See more: 10000*.08 - 10 Per Bag

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This is not sufficient information to decide if two triangles are congruent!

Because the triangles can have the same angles but be different sizes:

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is not congruent to:
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Without knowing at the very least one side, us can"t be certain if 2 triangles room congruent.


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