A matrix has eigenvalues $–1$ and $–2$. The corresponding eigenvectors are $\begin{bmatrix} 1\\-1 \end{bmatrix}$ and $\begin{bmatrix} 1\\-2 \end{bmatrix}$ respectibely. The matrix is
1. $\begin{bmatrix} 1 & 1\\ -1 & -2 \end{bmatrix}$
2. $\begin{bmatrix} 1 & 2\\ -2 & 4 \end{bmatrix}$
3. $\begin{bmatrix} -1 & 0\\ 0 & -2 \end{bmatrix}$
4. $\begin{bmatrix} 0& 1\\ -2 & 3 \end{bmatrix}$