About This Chapter
Angles & Triangles - Chapter Summary
This chapter is all about navigating angles and triangles in geometry. It aims to boost your students' understanding of relevant geometrical properties, forms of measurement, and mathematical applications. By the time your students finish going through these lessons, they'll be better prepared to apply knowledge of the following topics:
- Measuring the angles of a polygon
- Defining the interior and exterior angles of a triangle
- Triangular medians, altitudes, and angle bisectors
- Angles created by a transversal
- Like triangles and the AA criterion
- Solving problems with similar triangles
- The transitive property
With every lesson containing both a video and transcript of the content, you'll be able to select the way you want your students to learn each topic. If you watch the videos, you and your students can skip around main points of the material by means of the timeline feature, while readers of the transcripts will find key terms highlighted in bold.
1. How to Measure the Angles of a Polygon & Find the Sum
Watch this video lesson to learn the one formula that lets you find the measure of angles in any regular polygon. Also, learn how you can tell if you are working with a regular polygon or not.
2. Interior and Exterior Angles of Triangles: Definition & Examples
Knowing just a few things about the interior or exterior angles of triangles is sometimes all you need to put all the pieces together. Find out more in this lesson.
3. 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.
4. Angles Formed by a Transversal
When you have a pair of parallel lines and a transversal, something very interesting happens to the angles that are formed. You can see this happen in real life at street intersections and such. Watch this video lesson to learn about all of this.
5. Similar Triangles & the AA Criterion
This video lesson explains the AA criterion and shows you why you only need two corresponding angles to be equal for two triangles to be similar. You will also see how you can use it to help you identify similar triangles.
6. Applications of Similar Triangles
Similar triangles are used to solve problems in everyday situations. Learn how to solve with similar triangles here, and then test your understanding with a quiz.
7. The Transitive Property of Similar Triangles
Watch this video lesson and you will understand what the transitive property is and how it applies to similar triangles. Watch as we apply the transitive property to three similar triangles.
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Other chapters within the STAAR Mathematics - Grade 8: Test Prep & Practice course
- Mathematical Problem Solving
- Numerical Representations - Numbers & Operations
- Slope & Rate of Change
- Functions & Proportionality
- Geometric Transformations
- Geometric Expressions, Equations & Relationships
- Bivariate Data
- Personal Financial Literacy
- About the STARR Tests
- STAAR Mathematics - Grade 8 Flashcards