19. (4 points each) Solve the following system by using (a) Cramer's Rule, and (b) Gauss-Jordan elimination cty =4 2x - y = 11 20. (5 points) Solve the system by using matrix inversion. 3x + y =1 3x - 2y = -11 State whether the system is consistent/inconsistent, linearly depen- dent/independent, and whether the system has a unique solution, in- finitely many solutions, or no solution. 21. (5 points) Find all eigenvalues and eigenvectors of the matrix. Be sure to normalize the eigenvectors