-Ricky Bobby

Congruent Triangles
Postulate 4-1: Side-Side-Side (SSS) Postulate: If the three sides of one triangle are congruent to the three sides of another triangle, then the two triangles are congruent.
 GHF   PQR
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Proving Triangles Congruent
F
Given : H is the midpoint of GK
HF  HJ , FG  JK
Prove :  FGH   JKH
G
H
J
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Statements
1.
H is the midpoint of GK
2.
GH  KH
3.
HF  HJ , FG  JK
4.
 FGH   JKH
Reasons
1.
2.
3.
4.
K

Proving Triangles Congruent
B
Given : AB  CB , AD  CD
Prove :  ABD   CBD A
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Statements
1.
AB  CB , AD  CD
2.
BD  BD
3.
 ABD   CBD
Reasons
1.
2.
3.
D
C

Congruent Triangles
Postulate 4-2: Side-Angle-Side (SAS) Postulate: If two sides and an included angle of one triangle are congruent to two sides and an included angle of another triangle, then the two triangles are congruent.
 BCA   FDE
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Congruent Triangles
SSS, SAS, or NEI?

Proving Triangles Congruent

Can you use the following information to prove the triangles congruent?
A
Given : EB  CB , AE  DB
Prove :  AEB   DBC
E B
D
Not enough information to prove triangles congruent!!
C

Proving Triangles Congruent

Can you use the following information to prove the triangles congruent?
A
Given : EB  CB , AB  DB
Prove :  AEB   DBC
E B
D
Statements
1.
EB  CB , AB  DB
2.
 ABE   DBC
3.
 AEB   DBC
Reasons
1.
2.
3.
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
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C

Homework 4.2:
3, 6-9, 16-18,
20-25, 28-30
I was never a very good practical joker.
-Bill Murray