Download 4-3 Congruent Triangles.notebook

4­3 Congruent Triangles.notebook
October 29, 2014
ANGLES
Given Statement Reason
1
/ 1 + / 2 + / 3 = 180
2
Sum
3
/ 1& / 2 are complementary
acute angles in rt. 1
2
1
2
/ 1 = / 2 = / 3 = 60o
angles in equiangular 3
1
2
/ 1 + / 2 = / 3
Ext. angle thm
3
Chapter 4­3: Congruent Triangles
Congruence in Geometric Figures
Two geometric figures are congruent iff they have
exactly the same size and shape.
When two figures are congruent, there is a
correspondence between their angles and sides
such that corresponding angles and corresponding sides
are congruent.
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4­3 Congruent Triangles.notebook
October 29, 2014
CPCTC= CORRESPONDING PARTS OF CONGRUENT TRIANGLES ARE CONGRUENT!!!
Example 1
1) Write the congruence statement in another
order:
a) List the corresponding sides
b) List the corresponding angles
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4­3 Congruent Triangles.notebook
October 29, 2014
THIRD ANGLE THEOREM
If two angles in one triangle are
congruent to two angles in the other
triangle, then the third pair of angles
are congruent.
Example 2: Solve for the variable!
"Angles Tool Chest" (Put this right behind your other Tool Chest that you have already made!)
Given
Statement
Reason
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4­3 Congruent Triangles.notebook
October 29, 2014
Example 3
Example 3
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4­3 Congruent Triangles.notebook
October 29, 2014
Example 4
9. m / E ___________ Consecutive vertices are the endpoints of a side.
Always name a polygon using consecutive vertices.
24o
Homework Assignment #35:
p. 259: #9­16 all, 18­20 all, 29,37,49,53,55
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