Quick Question Classify these triangles in two different

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Quick Question: Classify these triangles in two different ways…one way using the sides, and

Quick Question: Classify these triangles in two different ways…one way using the sides, and the other way using the angles. Hint: What are some of the different types of triangles?

. SIDES Equilateral: C, F, Isosceles: A, D, Scalene: E, H, B ANGLES Right:

. SIDES Equilateral: C, F, Isosceles: A, D, Scalene: E, H, B ANGLES Right: D Obtuse: A, H Acute: B, C, E, F, G

Today’s Objective: I can use geometric theorems and postulates to find congruent triangles.

Today’s Objective: I can use geometric theorems and postulates to find congruent triangles.

What are some rules that you know about triangles?

What are some rules that you know about triangles?

Attempt to make triangles with the following side lengths. If the sides make a

Attempt to make triangles with the following side lengths. If the sides make a triangle, record the measure of each of the triangles measure. 3, 4, 5 Side Lengths Triangle Possible? 1, 1, 3 2, 4, 7 2, 3, 4 4, 5, 7 2, 3, 8 Triangle Possible? Sketch Triangle Side Lengths

Inv. 3 - Problem 3. 1: Building Triangles Virtual Polystrips http: //media. pearsoncmg. com/curriculum/math/cmp

Inv. 3 - Problem 3. 1: Building Triangles Virtual Polystrips http: //media. pearsoncmg. com/curriculum/math/cmp 3/activities/A 82391/index. html Side Lengths 3, 4, 5 1, 1, 3 2, 4, 7 Triangle Possible? 2, 3, 4 4, 5, 7 2, 3, 8 Triangle Possible? Sketch Triangle Side Lengths Answers on next pages

Virtual Polystrips http: //media. pearsoncmg. com/curriculum/math/cmp 3/activities/A 82391/index. html 3, 4, 5 1, 1,

Virtual Polystrips http: //media. pearsoncmg. com/curriculum/math/cmp 3/activities/A 82391/index. html 3, 4, 5 1, 1, 3 Yes! No 2, 4, 7 No 2, 3, 4 Yes!

4, 5, 7 Yes! 2, 3, 8 No

4, 5, 7 Yes! 2, 3, 8 No

Inv. 3 - Problem 3. 1: Building Triangles Virtual Polystrips http: //media. pearsoncmg. com/curriculum/math/cmp

Inv. 3 - Problem 3. 1: Building Triangles Virtual Polystrips http: //media. pearsoncmg. com/curriculum/math/cmp 3/activities/A 82391/index. html Side Lengths 3, 4, 5 1, 1, 3 2, 4, 7 Triangle Possible? Sketch Triangle Side Lengths Triangle Possible? Sketch Triangle No No 2, 3, 4 2, 4, 7 2, 3, 8 Yes! No Yes! Answers on next pages

What are some side lengths that made a triangle? What are some side lengths

What are some side lengths that made a triangle? What are some side lengths that could NOT make a triangle? 1, 1, 3 2, 4, 7 2, 3, 8

What pattern do you see that explains why some sets of numbers will make

What pattern do you see that explains why some sets of numbers will make a triangle and others do not? If the sum of two side lengths is less than the third length, no triangle can be constructed.

For what side length relationships can you make more than one triangle from a

For what side length relationships can you make more than one triangle from a given set of side lengths? In no case can a given set of side lengths be used to make two different triangle shapes.

Test your hypothesis: Find 3 other side lengths that will make a triangle. Then

Test your hypothesis: Find 3 other side lengths that will make a triangle. Then find 3 other side lengths that will not make a triangle.

Write a summary statement would help someone who is not here today know how

Write a summary statement would help someone who is not here today know how to judge whether three lengths will make a triangle without actually building the triangle.

Which sets form a triangle? Why? 4, 3, 5 8, 2, 12 8, 8,

Which sets form a triangle? Why? 4, 3, 5 8, 2, 12 8, 8, 4 4, 3, 5 and 8, 8, 4 because the sum of any two sides is greater than the third.

Do any of the triangles have special properties? Describe them. 8, 8, 4 is

Do any of the triangles have special properties? Describe them. 8, 8, 4 is isosceles since it has two equal sides. 4, 3, 5 is a right triangle because it has one 90 degree angle and is a scalene triangle since all sides have different lengths.