# Ch 26: Introduction to Proofs and Constructions

### About This Chapter

Use our video lessons and quizzes to help you understand geometric postulates. Learn to prove theorems for parallelograms, triangles, lines and angles.

## Introduction to Proofs and Constructions - Chapter Summary

If you're looking to get a better idea of the differences between proofs, theorems and postulates, this chapter is for you. Introductory lessons explain what theorems are used for and introduce you to the axiomatic systems and postulates used to derive them.

You can build on this knowledge to explore theorems relating to corresponding pairs of angles and sides as well as parallel or perpendicular lines. Instructors also walk you through the various postulates used to demonstrate the congruence of triangles or establish the relationships between triangle medians, midsegments and centroids.

You can also take a look at parallelogram theorems used to prove the congruence of opposite sides and angles, the supplementary nature of consecutive angles and the shapes formed by their diagonals. This chapter concludes with lessons that show you how to apply this knowledge by using compasses and rulers to create geometric shapes, such as equilateral triangles, squares, triangles and inscribed hexagons. Topics of instruction include:

• Axiomatic systems
• Triangle congruence postulates
• Postulates for lines and angles
• Triangle theorems
• Parallelogram theorems

Whether you choose to access lesson content in the form of short videos or corresponding transcripts, you'll get the benefit of our instructors' expertise. This chapter also includes self-checking, multiple-choice quizzes you can take as many times as you need.

9 Lessons in Chapter 26: Introduction to Proofs and Constructions
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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### Other Chapters

Other chapters within the TExES Mathematics 7-12 (235): Practice & Study Guide course

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