# What is a Quadratic Equation?

1. A quadratic equation is a polynomial equation of the second degree.
2. A quadratic equation has only one variable
3. The highest power of the variable is 2.
• $2{x}^{2}+3x+4=0$
• ${t}^{2}=\frac{2}{5}$
• $y\left(6y-3\right)=5$
• $a-3y+2{y}^{2}=2$ where a is a constant.
• $2x+1=0$ , (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 $\frac{5}{t}$ .)