Solve the following system of equations using matrices. Use Gaussian elimination with back substitution or Gauss-Jordan elimination.
a. 3x1 + 5x2 - 8x3 + 5x4 = -8
b. x1 + 2x2 - 3x3 + x4 = -7
c. 2x1 + 3x2 - 7x3 + 3x4 = -11
d. 4x1 + 8x2 - 10x3+ 7x4 = -10
my answer = B
Hard to type matrices and to line them up properly.
Try this effective applet
http://www.gregthatcher.com/Mathematics/GaussJordan.aspx