# What is a Quadratic Equation?

- A quadratic equation is a polynomial equation of the second degree.
- A quadratic equation has only one variable
- The highest power of the variable is 2.

**Example of Quadratic Equation**

The followings are some examples of quadratic equations

- $2{x}^{2}+3x+4=0$
- ${t}^{2}=\frac{2}{5}$
- $y(6y-3)=5$
- $a-3y+2{y}^{2}=2$ where a is a constant.

**Example of Non Quadratic Equation**

- $2x+1=0$ , (Reason: The highest power of x ≠ 2.)
- $2{x}^{3}+1=x$ , (Reason: The highest power of x ≠ 2.)
- ${t}^{2}+\frac{5}{t}=3$ , (Reason: The present of the term $\frac{5}{t}$ .)

**Example 1**