Question

solve this if A= (1 - 1 2) andB= (2 3 - 1 ), than find A+B, 3A+4B BY MATTRICE

Answer 1

(1 - 12) + (23 - 1)
= -11 + 22
= 11

3(1 - 12) + 4(23 - 1)
= (3 - 36) + (92 - 1)
= -33 + 91
=58