Is 7x3 a monomial?

Explanation:
A monomial is a product of a constant and variables raised to non-negative whole number powers.
Monomial Examples:
${\displaystyle 5x,\frac{2}{3}{a}^2,4x^3{y}^{2}z}$
Examples that may take some thought:
3, (Sometimes we say that this is ${\displaystyle 3x^0}$, since ${\displaystyle x^0=1}$ for all x except x =0)
0, (sometimes it is helpful to write this as ${\displaystyle 0x^2}$ or 0t)
${\displaystyle 7\sqrt{3}{x}^5}$, (It is ok for the constant to involve a root)
Not Monomials:
${\displaystyle \frac{2}{x}}$ (Monomials do not have variables in the denominator.)
${\displaystyle 5\sqrt{x}}$ (Monomials do not have roots of the variables.)
${\displaystyle 3x^2+7x}$ (This is a binomial.)