Row Reduction & Rank · Easy problem

A matrix has the factorization $A = LU$ with $L = \begin{pmatrix} 1 & 0 \\ 3 & 1 \end{pmatrix}$ and $U = \begin{pmatrix} 2 & 5 \\ 0 & -1 \end{pmatrix}$. What is the entry of $A$ in row 2, column 2?