Examine whether the following equation is quadratic or not: $x^{4}-5x^{2}+3x-1=0$.

(NO) Let the polynomial be $p(x) = x^{4}-5x^{2}+3x-1$.
The degree of a polynomial is the highest power of the variable present in the expression.
In the given polynomial $p(x)$,the highest power of $x$ is $4$.
$A$ quadratic equation is defined as an equation of the form $ax^{2}+bx+c=0$,where $a \neq 0$ and the degree of the equation is $2$.
Since the degree of the given polynomial is $4$,it is a biquadratic equation,not a quadratic equation.
Therefore,$x^{4}-5x^{2}+3x-1=0$ is not a quadratic equation.