Linear Algebra - Eigenvalues

Pick the CORRECT eigen value(s) of the matrix [A] from the following choices. [A] = [[6, 8], [4, 2]]

What are the eigenvalues of the matrix $\begin{bmatrix} 2 & 1 & 1 \\ 1 & 4 & 1 \\ 1 & 1 & 2 \end{bmatrix}$?

If M is an arbitrary real n x n matrix, then which of the following matrices will have non-negative eigenvalues?

The matrix M is defined as $M = \begin{bmatrix} 1 & 3 \\ 4 & 2 \end{bmatrix}$ and has eigenvalues 5 and -2. The matrix Q is formed as $Q = M^3 - 4M^2 - 2M$ Which of the following is/are the eigenvalue(s) of matrix Q?

Consider the following simultaneous equations (with c₁ and c₂ being constants): 3 x₁ + 2 x₂ = c₁ 4 x₁ + x₂ = c₂ The characteristic equation for these simultaneous equations is