Hi, there-- 3x -y + z = 4 x + 2y + 3z = 10 3x + 2y -z = -12 The augmented matrix for this system isHere is a very helpful site for showing the row operations to solve a matrix. The calculator will solve the matrix and show you all the steps, or it will let you practice by choosing each row operation yourself. (Great learning tool!) http://www.math.odu.edu/~bogacki/cgi-bin/lat.cgi?c=roc The correct answer is C. (-1, -2, 5). Good luck! Mrs. Figgy