# Ch 14: Geometry

Watch online geometry video lessons to learn about triangles, rectangles, circles, the Pythagorean theorem, and more. Each lesson is accompanied by a short multiple-choice quiz you can use to check your understanding of these topics.

## Geometry

In our series of lessons, you'll learn about the properties, areas, and perimeters of basic geometric shapes, such as triangles, circles, and rectangles. You'll learn the properties of these shapes and how you can identify them. For instance, you'll determine that a triangle is a polygon with three sides, while a rectangle is a quadrilateral with four sides joined at 90 degree angles. To help you discern the differences of these shape properties, we'll define terminology, such as vertex, radius, diameter, polygon, angle, right angle, acute angle, obtuse angle, equilateral triangle, scalene triangle, isosceles triangle, altitude, base, and plane.

Once you understand the basic properties of these shapes, you'll study their perimeters (the lines that outline the shapes), as well as their areas (the amount of space within the shapes).

Continuing on with triangles, you'll study the Pythagorean theorem, a theorem used to calculate the length of a triangle's side. You may even recognize this easy-to-remember equation: a^2 + b^2 = c^2. In other words, side a squared plus side b squared equals side c squared, which is the longest side, also known as the hypotenuse. After learning the Pythagorean theorem, you'll solve plenty of practice problems and learn some real-life applications of the theorem.

So, if your skills can use some sharpening, these video lessons can help you get back into shape. Thanks for watching!

Final Exam
Chapter Exam

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