By Rational Root Theorem, all rational roots of a polynomial are in the form $\frac{p}{q}$, where $p$ divides the constant term $-32$ and $q$ divides the leading coefficient $1$. One such root is $2$. Factor the polynomial by dividing it by $x-2$. Polynomial $x^{4}+2x^{3}+4x^{2}+8x+16$ is not factored since it does not have any rational roots.
