About This Chapter
Who's it for?
Anyone who needs help understanding high school geometry material will benefit from taking this course. You will be able to grasp the subject matter faster, retain critical knowledge longer and earn better grades. You're in the right place if you:
- Have fallen behind in understanding the properties of parallel lines and polygons.
- Need an efficient way to learn about parallel lines and polygons.
- Learn best with engaging auditory and visual tools.
- Struggle with learning disabilities or learning differences, including autism and ADHD.
- Experience difficulty understanding your teachers.
- Missed class time and need to catch up.
- Can't access extra math learning resources at school.
How it works:
- Start at the beginning, or identify the topics that you need help with.
- Watch and learn from fun videos, reviewing as needed.
- Refer to the video transcripts to reinforce your learning.
- Test your understanding of each lesson with short quizzes.
- Submit questions to one of our instructors for personalized support if you need extra help.
- Verify you're ready by completing the Parallel Lines and Polygons chapter exam.
Why it works:
- Study Efficiently: Skip what you know, review what you don't.
- Retain What You Learn: Engaging animations and real-life examples make topics easy to grasp.
- Be Ready on Test Day: Use the Parallel Lines and Polygons chapter exam to be prepared.
- Get Extra Support: Ask our subject-matter experts any relevant question. They're here to help!
- Study With Flexibility: Watch videos on any web-ready device.
Students will review:
In this chapter, you'll learn the answers to questions including:
- What types of angles are formed by a transversal?
- What are the theorems for proving lines are parallel?
- How can you construct a parallel line with a point not on the given line?
- What is the relationship between indirect proof and the parallel postulate?
- What is the definition of a polygon?
- How do you calculate the number of diagonals in a polygon?
- What formulas do you use to determine the area or perimeter of a polygon?
- How do you measure the angles of polygons and triangles?
1. 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.
2. Parallel Lines: How to Prove Lines Are Parallel
Watch this video lesson to learn how you can prove that two lines are parallel just by matching up pairs of angles. Learn which angles to pair up and what to look for.
3. Using Converse Statements to Prove Lines Are Parallel
Because a pair of parallel lines produces unique angle characteristics, we can use this information to our advantage. Watch this video lesson to see how we turn this advantage into converse statements to help us prove parallel lines.
4. Constructing a Parallel Line Using a Point Not on the Given Line
Watch this video lesson, and you will learn how to draw parallel lines with just a compass and a straightedge. Also, learn why you would want to be able to do this in real life.
5. The Parallel Postulate: Definition & Examples
In this lesson, you will learn about an important postulate in Euclidean geometry, called the Parallel Postulate. It sounds kind of hard, but this lesson explains it in simple terms and provides several examples of it as well.
6. What Are Polygons? - Definition and Examples
Watch this video lesson to see how the shapes that you grew up with are all related. Learn why the shapes of bricks, stars, and street blocks are considered polygons while the sun, moon, and rolling hills are not.
7. Regular Polygons: Definition & Parts
What makes a polygon a polygon? And what shapes are considered polygons? In this lesson, find out the answers to these questions and more as we learn all about polygons and their parts.
8. How to Find the Number of Diagonals in a Polygon
At first, you might think that the diagonals of a polygon are pretty useless, but watch this video lesson to learn how diagonals are used in real life. You will learn the formula to find how many diagonals a polygon has as well as how to use it.
9. Finding the Perimeter of Polygons
In this video lesson, you will learn the process you need to take to find the perimeter of polygons. You will also learn that there is a shortcut if your polygon is a regular polygon.
10. Measuring the Area of Regular Polygons: Formula & Examples
Watch this video lesson to learn why a regular polygon makes your life easier when it comes to finding the area inside one. Learn the one formula for area that will work for any type of regular polygon.
11. Measuring the Angles of Triangles: 180 Degrees
Watch this video lesson to see why a triangle's angles always add up to 180 degrees. Also, learn how you can use this unique fact about triangles to find an unknown angle in a triangle.
12. 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.
13. Decagon: Definition & Shape
In this lesson, we'll discuss the different types of decagons, such as regular and irregular, convex and concave, and simple and complex. Then, you can test your knowledge with a brief quiz.
14. Parallel Sides: Definition & Concept
In this lesson, you will learn the special properties of parallel sides. Only certain shapes have the distinguished honor of having parallel sides. Learn what these are and discover how to mathematically mark two sides that are parallel.
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Other chapters within the High School Geometry: Help and Review course
- Foundations of Geometry: Help and Review
- Logic in Mathematics: Help and Review
- Introduction to Geometric Figures: Help and Review
- Properties of Triangles: Help and Review
- Triangles, Theorems and Proofs: Help and Review
- Similar Polygons: Help and Review
- Quadrilaterals: Help and Review
- Circular Arcs and Circles: Help and Review
- Conic Sections: Help and Review
- Geometric Solids: Help and Review
- Analytical Geometry: Help and Review
- Introduction to Trigonometry: Help and Review