Step 1: Define the characteristic equation. The characteristic equation is derived from the determinant of \( A - \lambda I \), leading to \( \lambda^2 - 8\lambda + 7 = 0 \).
Step 2: Calculate the determinant and simplify. The determinant simplifies to \( \lambda^2 - 8\lambda + 7 \), which factors to find the eigenvalues.
Step 3: Solve for \( \lambda \). Using the quadratic formula, we find the solutions to be \( \lambda = 7 \) and \( \lambda = 1 \), confirming the eigenvalues of the matrix.