Which operation can be used with the augmented matrix? the 3 by 4 matrix, row 1, column 1, 3 column 2, negative 2 column 3, 1 column 4, 15 row 2, column 1, 1 column 2, 5 column 3, 8 column 4, 15 row 3, column 1, negative 2 column 2, negative 1 column 3, 3 column 4, 1