Compute each matrix sum or product if it is defined. If an expression is undefined, explain why. Let A = [[3, 0, −1], [5, −5, 4]], B = [[7, −6, 1], [2, −4, −4]], C = [[1, 2], [−1, 1]], D = [[4, 4], [−2, 3]], and E = [−6, 2]ᵀ.

A + 3B, 4C − 2E, DB, EB