In Problem, write each system as a matrix equation and solve using the inverse coefficient matrix. Use a graphing calculator or computer to perform the necessary calculations.
3x1 + 3x2 + 6x3 + 5x4 = 10
4x1 + 5x2 + 8x3 + 2x4 = 15
3x1 + 6x2 + 7x3 + 4x4 = 30
4x1 + x2 + 6x3 + 3x4 = 25