6. Consider the system of linear equations + x2 + 2x3 = 3 2x1 + 6x2 53 = 2 -3x1 + 7x2 5x3 = -1 1. Verify that (1, 3, 2. Verify that C 3 1) is a solution of the system. 7. 4) is a solution of the system. - 3. Determine if the vector b (3, 2, 1) is a linear combination of the column vectors of the coefficient matrix of the system. 4. Determine if the vector b = (3, 2, 1) belongs to the spanning space of the column vectors of the coefficient matrix of the system.