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Solve for x:
7x­3
4x+7
4.1 Classifying Triangles
p.237­238
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4.2 Angles in Triangles
Triangle Sum: the sum of the interior angles of a triangle equals 180
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Exterior Angle Theorem:
the sum of the remote interior angles equals the exterior angle
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What are the angle measures of the equilateral triangle below?
Equiangular: all the angles are equal
Triangles are equilateral if and only if they are equiangular.
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What is the type of triangle?
40
x
y
What is the measure of x and y?
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4.3 Congruent Triangles
Congruent Polygons have congruent corresponding parts.
If figures are congruent, their corresponding parts are congruent regardless of the way the figures are turned or flipped.
A
D
B
E
E
C
C
A
D
B
You must be able to name the congruent parts of congruent polygons.
Congruency Statement:
Are these 2 triangles congruent?
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Are these pairs of figures congruent?
EF is parallel to HG
Homework:
p. 241 #21­26
p. 250 #12­20 even
p. 259 #13­16
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