## Prove theorems about triangles. Theorems include: measures of interior angles of a triangle sum to 180 degrees; base angles of isosceles triangles are congruent; the segment joining midpoints of two sides of a triangle is parallel to the third side and half the length; the medians of a triangle meet at a point.

48 Lesson(s)

### Tremendous Triangles Projects

Geometry » Unit: Tremendous Triangles
Geometry » Unit: Tremendous Triangles
Saratoga Springs, NY
Environment: Suburban

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Favorites (9)

Resources (12)

Reflections (1)

### The Rope Stretcher

Geometry » Unit: Area Relationships
Geometry » Unit: Area Relationships
Ault, CO
Environment: Rural

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Favorites (10)

Resources (26)

### Mid-Segment Maylay

Geometry » Unit: Three Triangle Topics
Geometry » Unit: Three Triangle Topics
Saratoga Springs, NY
Environment: Suburban

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Favorites (8)

Resources (19)

Reflections (2)

### Group Assessment: Triangle Congruence and Proof

Geometry » Unit: Discovering and Proving Triangle Properties
Geometry » Unit: Discovering and Proving Triangle Properties
Sunnyvale, CA
Environment: Suburban

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Favorites (8)

Resources (11)

Reflections (1)

### What Are We Gonna Learn?

Geometry » Unit: Area Relationships
Geometry » Unit: Area Relationships
Ault, CO
Environment: Rural

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Standards:

Favorites (3)

Resources (24)

### Left-Over Squares

Geometry » Unit: Area Relationships
Geometry » Unit: Area Relationships
Ault, CO
Environment: Rural

Big Idea:

Standards:

Resources (29)

### Shifty Shears

Geometry » Unit: Area Relationships
Geometry » Unit: Area Relationships
Ault, CO
Environment: Rural

Big Idea:

Standards:

Resources (26)

### Triangle Congruence and CPCTC Practice

Geometry » Unit: Discovering and Proving Triangle Properties
Geometry » Unit: Discovering and Proving Triangle Properties
Sunnyvale, CA
Environment: Suburban

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Standards:

Favorites (11)

Resources (11)

### Discovering and Proving Triangle Properties Unit Assessment

Geometry » Unit: Discovering and Proving Triangle Properties
Geometry » Unit: Discovering and Proving Triangle Properties
Sunnyvale, CA
Environment: Suburban

Big Idea:

#### In this unit assessment, students will demonstrate their understanding of triangle congruence and proof in a series of multiple choice, open-ended, and proof-based questions.

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Favorites (2)

Resources (5)

Geometry » Unit: Proofs about Triangles
New York, NY
Environment: Urban

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Favorites (13)

Resources (13)

Reflections (1)

### CPCTC

Geometry » Unit: Proofs about Triangles
Geometry » Unit: Proofs about Triangles
New York, NY
Environment: Urban

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Standards:

Favorites (5)

Resources (14)

### Angle-Side-Angle

Geometry » Unit: Proofs about Triangles
Geometry » Unit: Proofs about Triangles
New York, NY
Environment: Urban

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Favorites (3)

Resources (18)

Reflections (1)

### Angles of a Triangle

Geometry » Unit: Parallel Lines
Geometry » Unit: Parallel Lines
Amsterdam, NY
Environment: Urban

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Favorites (17)

Resources (23)

Reflections (1)

### Time for Triangles

Geometry » Unit: Tremendous Triangles
Geometry » Unit: Tremendous Triangles
Saratoga Springs, NY
Environment: Suburban

Big Idea:

#### Students will measure, cut and measure again to learn and prove key properties of triangles

Standards:

Favorites (3)

Resources (28)

Reflections (2)

Geometry » Unit: Proofs about Triangles
New York, NY
Environment: Urban

Big Idea:

Standards:

Resources (16)

Reflections (1)
Common Core Math