Download Lesson 5.5.notebook

Lesson 5.5.notebook
December 04, 2012
Warm‐up
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Lesson 5.5.notebook
December 04, 2012
Warm‐up
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Lesson 5.5.notebook
December 04, 2012
Page 283 Homework Answers
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Lesson 5.5.notebook
December 04, 2012
Lesson 5.5 ‐ Inequalies in Triangles
Comparison Property of Inequality
If a = b + c and c > 0, then a > b
Corollary to the Triangle Exterior Angle Theorem
The measure of an exterior angle of a triangle is greater than the measure of each of its remote interior angle.
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Lesson 5.5.notebook
Ex 1:
December 04, 2012
Explain why m<4 > m<5.
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Lesson 5.5.notebook
December 04, 2012
Theorem 5.10
If two sides of a triangle are not congruent, then the larger angle lies opposite the longer side.
Theorem 5.11
If two angles of a triangle are not congruent, then the longer side lies opposite the larger angle.
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Lesson 5.5.notebook
December 04, 2012
Ex 2: In ΔRGY, RG = 14, GY = 12, and RY = 20. List the angles from largest to smallest.
Ex 3:
List the sides of ΔXYZ in order from shortest to longest.
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Lesson 5.5.notebook
December 04, 2012
*** The lengths of three segments must be related in a certain way to form a triangle ***
Theorem 5.12 ‐ Triangle Inequality Theorem
The sum of the lengths of any two sides of a triangle is greater than the length of the third side.
Ex 4:
Can a triangle have sides with the given lengths? Explain.
a) 2 m, 7 m, 9 m
b) 4 yd, 6 yd, 9 yd
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Lesson 5.5.notebook
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Ex 5: A triangle has sides of lengths 3 in. and 12 in. Describe the lengths possible for the third side.
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Lesson 5.5.notebook
December 04, 2012
Homework: Page 292 #1‐28, 32‐37
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