# Equation Defintion

In Mathematics, an **equation** shows that two **expressions** are **equal** to each other. An equation, in **Algebra**, can involve multiple **variables**, **constants**, and **terms**. For example, **2x + 4 = 9** is an equation as it is showing that **2x + 4** and **9** (both are expressions) are **equal** to each other.

**Note:**

Read about Expressions, Variables, Constant, and Terms here.

**Table of Contents**

## Representation of an equation

To represent **equality** between two **terms** or **expressions**, a sign of “=” is put between those terms. It means that “=” is the sign that represents the overall term as an equation.

**For example, **, if we have two expressions **5x + 7** and **2y + 11**, and want to show them in the form of an equation, we will put “=” between them as shown below.

5x + 7 = 2y + 11

### Parts of an equation

As mentioned above, an equation is a **connection** between **different expressions**. An **expression** is also made from different **terms**. It means that an **equation** has multiple **parts** involving those of an **expression** too. Here are the major parts of an equation.

- Variable
- Term
- Operator
- Sign of equality
- Constant

An equation can involve any of these parts but the sign of equality will always be there as it is the basic condition.

**Note:**

Read about **Operator** here.

### Types of equations

Depending on the degree of the variable, equations can be divided into three major types. Here we have enlisted those types with a brief discussion.

**Linear equations**: All those equations in which the **maximum degree** of the variable is “**1**” are called **linear equations**. For example, **2x + 4 = 9** is a linear equation because “**x**” has a maximum degree of “**1**”.

**Note:**

Read about **Linear equations** here.

**Quadratic equations**: The equations in which the **maximum degree** of variable is “**2**” will be termed **quadratic equations**. For example, **〖2x〗^2-3x+17=12** is a quadratic equation because the degree of “**x**” is “**2**”.

**Note:**

Read about **Quadratic equations **here.

**Cubic equations**: Those equations in which the variable has a **maximum degree of “3”** are called **cubic equations**. For example, 〖**12y〗^3 〖+ 2y〗^2-3y+127=162** is a cubic equation because the maximum power of “**y**” is “**3**”.

**Note:**

Read about **Cubic equations** here.

### Are expression and equation the same?

No, these are not the same. An **expression** is the collection of different **terms** without any **equality** or **inequality** sign. For example, **3x + 15** is an **expression**. On the other side, the **equation** shows that the given **expressions** are **equal** to each other by putting a sign of **equality** between them.

### How can we solve equations in Mathematics?

We can **solve** Mathematical **equations** by following all basic operators like addition**, Subtraction, Division**, and **Multiplication**. It depends on the operators involved in an equation and the degree of the equation.

### Fun Facts about Equations

### FAQ's

**Define an equation with an example.**

An equation shows that two given expressions are equal to each other. For example, 3y + 17 = 67 is an equation it shows that two expressions are equal.

**What are the three main types of equations?**

Depending on the degree of the variable, equations have three major types. Here are those types:

- Linear equations
- Quadratic equations
- Cubic equations

**Can we write the equation of a circle?**

Yes, we can write an equation of a circle. In fact, all Geometrical diagrams have specific equations to get their solution.