Download 4.4ааProving Triangles Congruent ASA and AAS OBJаааProve

4.4 Proving Triangles Congruent ASA and AAS
OBJ Prove triangles are congruent using ASA and AAS
Included angles were discussed in 4.3.
Included sides. Angle Side Angle (ASA) Congruence Postulate ­ If 2 angles and the included side of one triangle are congruent to 2 angles and the included side of a second triangle, then the 2 triangles are congruent. 1
Angle Angle Side (AAS) Congruence Theorem ­ If two angles and a nonincluded side of one triangle are congruent to two angles and the corresponding nonincluded side of a second triangle, then the two triangles are congruent. Prove the theorem.
Given:
Prove: 1)
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Developing a proof How do you know triangles are congruent? Look for 1) SSS
2) ASA
3) SAS
4) AAS
There is more than one way to prove most theorems.
__ __ ___ ___ Given: AD || EC BD ≡ BC
Prove: ABD __ __ __ ___ 1) AD || EC BD ≡ EBC
≡ BC 1) Given
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page 223 2 ­ 7 Let's work together.
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4.4 Assignment page 223 8 ­ 22, 26, 28, 32 ­ 38 even
19 ­ 3 steps
20 ­ 5 steps
21 ­ 3 steps
22 ­ 3 steps
Need graph paper
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