About This Chapter
How it works:
- Identify the lessons in the McDougal Littell Geometry Textbook Properties of Triangles chapter with which you need help.
- Find the corresponding video lessons within this companion course chapter.
- Watch fun videos that cover the properties of triangles topics you need to learn or review.
- Complete the quizzes to test your understanding.
- If you need additional help, rewatch the videos until you've mastered the material or submit a question for one of our instructors.
Students will learn:
- Perpendicular bisector theorem
- Angle bisector theorem
- Perpendicular bisectors of a triangle
- Concurrency of perpendicular bisectors of a triangle
- Concurrency of angle bisectors of a triangle
- Constructing the median of a triangle
- Median, altitude and angle bisectors of a triangle
- Proving theorems about triangles: Triangle medians and the centroid
- Identifying the mid-segments of a triangle
- Proving theorems about triangles: Triangle mid-segments theorem
- Comparing measurements of a triangle
- Theorems of inequality
- Triangle inequality
- Using indirect proof
- Hinge theorem
McDougal Littell Geometry is a registered trademark of McDougal Littell, which is not affiliated with Study.com.
1. Perpendicular Bisector Theorem: Proof and Example
Perpendicular bisectors are multifunctional lines. They're not only perpendicular to the line in question, they also neatly divide it into two equal halves. In this lesson, we'll learn about the perpendicular bisector theorem.
2. Angle Bisector Theorem: Proof and Example
The angle bisector theorem sounds almost too good to be true. In this lesson, we set out to prove the theorem and then look at a few examples of how it's used.
3. Constructing the Median of a Triangle
If you have one triangle and want to divide it, you can use a median line. Medians have special geometric properties that we'll learn about in this lesson.
4. Median, Altitude, and Angle Bisectors of a Triangle
Line segments in triangles are just clutter; they have special names and qualities depending on how they're drawn. In this lesson, we'll learn about medians, altitudes and angle bisectors.
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Other chapters within the McDougal Littell Geometry: Online Textbook Help course
- McDougal Littell Geometry Chapter 1: Basics of Geometry
- McDougal Littell Geometry Chapter 2: Reasoning and Proof
- McDougal Littell Geometry Chapter 3: Perpendicular and Parallel Lines
- McDougal Littell Geometry Chapter 4: Congruent Triangles
- McDougal Littell Geometry Chapter 6: Quadrilaterals
- McDougal Littell Geometry Chapter 7: Transformations
- McDougal Littell Geometry Chapter 8: Similarity
- McDougal Littell Geometry Chapter 9: Right Triangles and Trigonometry
- McDougal Littell Geometry Chapter 10: Circles
- McDougal Littell Geometry Chapter 11: Area of Polygons and Circles
- McDougal Littell Geometry Chapter 12: Surface Area and Volume