Download Chapter 5

Chapter 5
Triangle properties
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C – 25 The sum of the measures of the
angles of a triangle is 180°
C - 26 If two angles of one triangle are
equal in measure to two angles of another
triangle, then the third angle in each
triangle is equal. (Third angle Conjecture)
Lesson 5.2
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C – 27 If a triangle is isosceles, then its
base angles are congruent. (Isosceles
Triangle conjecture)
C – 28 If a triangle has two congruent
angles, then it is an isosceles triangle.
(Converse of the Isosceles Triangle
conjecture)
C – 29 An equilateral triangle is
equiangular and conversely, an
equiangular triangle is equilateral.
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Lesson 5.3
C – 30 The sum of the lengths of any two
sides of a triangle is greater than the
length of the third side (Triangle
Inequality conjecture)
C – 31 In a triangle, the longest side is
opposite the angle with the greatest
measure and the shortest side is opposite
the angle with the least measure. (Sideangle Inequality conjecture)
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C – 32 The measure of an exterior angle
of a triangle is equal to the measures of
the remote interior angles (Triangle
Exterior Angle conjecture)
m ABC = 50.27
m BAC = 69.41
A
50.27+69.41 = 119.68
m ACD = 119.68
B
C
D
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Lesson 5.4
C – 33 If the three sides of one triangle
are congruent to the three sides of
another triangle, then the triangles are
congruent. (SSS Congruent Conjecture)
C – 34 If two sides and the angle between
them in one triangle are congruent to two
sides and the angle between them in
another triangle, then the triangles are
congruent. (SAS Congruent conjecture)
Lesson 5.5
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C – 35 If two angles and the side between them
in one triangle are congruent to two angles and
the side between them in another triangle, then
the triangles are congruent. (ASA Congruent
conjecture)
C – 36 If two angles and a side that is not
between them in one triangle are congruent to
the corresponding two angles and side not
between them in another triangle, then the
triangles are congruent. (SAA Congruent
conjecture)
Lesson 5.6
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CPCTC – Corresponding parts of
congruent triangles are congruent.
A
Given: AR  ER, EC  AC
Show:
E A
C
B
D
1.
1. Given
2.
2. Given
3
3
4
5
4
5 CPCTC
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Lesson 5.7
C – 37 In an isosceles triangle, the
bisector of the vertex angle is also the
altitude to the base and the median to the
base. (Vertex Angle Bisector conjecture)