# Ch 4: High School Geometry: Properties of Triangles

Watch online video lessons and learn about the properties and construction of triangles. These easy-to-follow lessons are just a portion of our online study guide and video collection.

## High School Geometry: Properties of Triangles - Chapter Summary and Learning Objectives

You can learn the formulas to find the area and perimeter of triangles and rectangles in these lessons, and then work your way through the practice problems for additional support. Discover how to classify triangles by their sides and angles, in addition to learning ways to identify similar triangles. When you finish this chapter, you should be able to:

• Construct triangles
• Understand the properties of dilations
• Construct the median of a triangle
• Find the median, altitude and angle bisectors of triangles

Video Objectives
Triangles: Definition and Properties Define and illustrate a triangle. Identify the parts of a triangle.
Area of Triangles and Rectangles Learn to find the area of triangles and rectangles and apply that knowledge to find the areas of other related shapes.
Classifying Triangles by Angles and Sides Explain how to classify triangles by their sides and angles. Describe common types of triangles.
Perimeter of Triangles and Rectangles Learn perimeter of triangles and rectangles and apply to solve various problems.
Interior and Exterior Angles of Triangles Define and identify the interior and exterior angles of a triangle, providing examples.
How to Identify Similar Triangles Learn how to identify similar triangles through an understanding of corresponding, proportional and included angle parts.
Angles and Triangles: Practice Problems Gain practice solving for angles and triangles.
Constructing the Median of a Triangle Describe how to construct the median of a triangle, providing examples.
Median, Altitude, and Angle Bisectors of a Triangle Define median, altitude and angle bisectors of a triangle. Demonstrate how to identify those in an example.
Constructing Triangles Explain how to construct a triangle that is congruent to a given triangle. Demonstrate how to construct a triangle with two sides and the included angle.
Properties of Concurrent Lines in a Triangle Discuss properties, including centroid, altitude, angle bisector, incenter and orthocenter.
Properties of Dilations Understand that a dilation takes a line not passing through the center of the dilation to a parallel line, and leaves a line passing through the center unchanged.

11 Lessons in Chapter 4: High School Geometry: Properties of Triangles
Test your knowledge with a 30-question chapter practice test
Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
Not Taken
Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
Not Taken

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