please bantu di jawab ya.

Kesamaan Matriks

A = B
4a = 12 --> a = 3
-3b = 3a --> -b = a  = 3 --> b = - 3
3c = b --> 3c = -3 -->c = - 1

a + b + c = 3 - 3  - 1
a + b+ c = -1