Answer
Characteristic polynomial: $\lambda^2-4\lambda -45$
$\lambda = -5, 9$
Work Step by Step
1.) To find the characteristic polynomial, find $det(A-\lambda I)$
$=(2-\lambda)(2-\lambda)-49$
$=\lambda^2-4\lambda-45$
2.) Solve for the eigenvalues by equating the characteristic equation to zero and solving for $\lambda$
$\lambda^2-4\lambda-45=0$
$(\lambda+5)(\lambda-9) = 0$
$\lambda=-5,9$