## Elementary Algebra

$3xy^{2}$
Raising each term in the expression to the power of $1/2$, we obtain: $(9x^{2}y^{4})^{\frac{1}{2}}$ =$(9)^{\frac{1}{2}}(x^{2})^{\frac{1}{2}}(y^{4})^{\frac{1}{2}}$ =$3(x^{2\times\frac{1}{2}})y^{4\times\frac{1}{2}}$ =$3(x^{1})(y)^{2}$ =$3xy^{2}$