# Ch 39: Two-Dimensional Shapes

### About This Chapter

## Two-Dimensional Shapes - Chapter Summary

Watch the following lessons to review two-dimensional shapes like squares, polygons, parallelograms, and rhombuses. You'll also cover The information provided in this chapter includes:

- Properties of triangles
- Triangle classification
- Interior, exterior, central and inscribed angles
- Shapes such as kites, rectangles and trapezoids
- Parts of circles
- Calculations for the radius and diameter of circles

In this chapter, you will examine concepts and facts about two-dimensional shapes through video lessons and practice quizzes. Each lesson comes with a full written transcript and can be accessed on any mobile device. Study on-the-go using your laptop, tablet, or smartphone.

### 1. Triangles: Definition and Properties

What makes a shape a triangle? In this lesson, we'll explore the definition of a triangle, then analyze the parts of triangles, including the vertices, base and height.

### 2. Classifying Triangles by Angles and Sides

Not all triangles are the same. There are equilateral, isosceles and scalene triangles. Then there are right, acute and obtuse triangles. In this lesson, we'll learn how to classify triangles using their sides and angles.

### 3. 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.

### 4. Angles and Triangles: Practice Problems

Want more practice solving with angle pairs? How about more review for solving angles in triangles? Look no further. Get more practice here, and test your ability with a quiz.

### 5. What is a Quadrilateral? - Definition, Properties, Types & Examples

This lesson explains the definition and properties of a quadrilateral. We will look at examples of two categories of quadrilaterals. At the end, you will be able to test your knowledge with a quiz.

### 6. Parallelograms: Definition, Properties, and Proof Theorems

Watch this video lesson to learn how you can identify parallelograms. You will see the unique properties that belong to the parallelogram. You will see the special side and angle characteristics needed to prove a certain shape is a parallelogram.

### 7. What Is a Rhombus? - Definition and Properties

Watch this video lesson to learn why rhombuses are a special type of quadrilateral. Also, learn why a rhombus is also a parallelogram. Watch as we explore the sides and angles of a rhombus.

### 8. Kites in Geometry: Definition and Properties

A kite in geometry looks a lot like a kite in the sky! Watch this video lesson to see for yourself. Also, learn about the side and angle properties of kites that make them unique.

### 9. Rectangles: Definition, Properties & Construction

Watch this video lesson to learn a bit about rectangles. Learn why rectangles are the building blocks of many homes. Also, learn about the properties that make a rectangle unique from other shapes. Finally, learn how you can draw one.

### 10. Squares: Definition and Properties

Squares can be found in many places in the real world. Watch this video lesson to see how useful they can be and also to learn how to find the perimeter and area of a square.

### 11. Trapezoids: Definition and Properties

Watch this video lesson to learn what a trapezoid has to do with a triangle. Also, learn the special words that describe the various parts of a trapezoid. You will also see special types of trapezoids.

### 12. 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.

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### Other Chapters

Other chapters within the MTLE Middle Level Mathematics: Practice & Study Guide course

- 6th-8th Grade Math: Basic Arithmetic Operations
- 6th-8th Grade Math: Properties of Numbers
- Number Theory & Factoring
- 6th-8th Grade Math: Estimating & Rounding
- 6th-8th Grade Math: Whole Numbers
- 5th Grade Math: Simplifying Whole Number Expressions
- Negative Numbers
- 6th-8th Grade Math: Absolute Value
- 6th-8th Grade Math: Integers
- 6th-8th Grade Math: Rational Numbers
- 6th-8th Grade Math: Inequalities
- 6th-8th Grade Math: Introduction to Fractions
- 6th-8th Grade Math: Operations with Fractions
- 6th-8th Grade Math: Introduction to Decimals
- 6th-8th Grade Math: Operations with Decimals
- 6th-8th Grade Math: Percents
- Working with Rates, Ratios & Proportions
- Practical Applications of Rates, Ratios & Proportions
- Introduction to Exponents
- Working with Exponential Expressions
- Understanding Square Roots & Radical Expressions
- Radical Expressions & Equations
- Imaginary & Complex Numbers
- 6th-8th Grade Algebra: Writing Algebraic Expressions
- Basic Algebraic Expressions & Factoring
- Algebraic Distribution
- 6th-8th Grade Algebra: Writing & Solving One-Step Equations
- 6th-8th Grade Algebra: Writing & Solving Two-Step Equations
- 6th-8th Grade Algebra: Simplifying & Solving Rational Expressions
- 6th-8th Grade Algebra: Linear Equations
- 6th-8th Grade Algebra: Systems of Linear Equations
- 6th-8th Grade Algebra: Monomials & Polynomials
- 6th-8th Grade Math: Properties of Functions
- 6th-8th Grade Math: Graphing Functions
- Rate of Change Basics
- Notation, Sequences & Series
- 6th-8th Grade Measurement: Units of Measurement
- Fundamentals of Geometric Figures & Angles
- Circle Geometry
- The Pythagorean Theorem & Trigonometry
- 6th-8th Grade Measurement: Perimeter & Area
- 6th-8th Grade Geometry: Polyhedrons & Geometric Solids
- Congruence & Similarity in Geometry
- 6th-8th Grade Math: The Coordinate Graph
- 6th-8th Grade Geometry: Transformations
- Modeling to Solve Problems
- Basic Probability
- Statistics & Sampling Basics
- MTLE Middle Level Mathematics Flashcards