Proving RightTriangles Congruent

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Proving RightTriangles Congruent
Free powerpoints at http//www.worldofteaching.com
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The Idea of a Congruence
Two geometric figures with exactly the same
size and shape.
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How much do you need to know. . .
. . . about two triangles to
prove that they are congruent?
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Corresponding Parts
In Lesson 4.2, you learned that if all six pairs
of corresponding parts (sides and angles) are
congruent, then the triangles are congruent.
?ABC ? ? DEF
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Do you need all six ?
NO !
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Do you need to use these for right triangles ?
NO !
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Right triangle vocabulary

• Leg hypotenuse
• leg
• Since you know the right angles always match you
  only need two more parts to be congruent.

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LL leg - leg
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LA leg - angle
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HA hypotenuse - angle
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HL hypotenuse - leg
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Name That Postulate
(when possible)
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Lets Practice
Indicate the additional information needed to
enable us to apply the specified congruence
postulate.
For ASA
?B ? ?D
For SAS
?A ? ?F
For AAS
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HW
Indicate the additional information needed to
enable us to apply the specified congruence
postulate.
A

For LA
B
C
D
For LL
F
E