Write the system of equation as a matrix equation of the form AX=B
X1-2x2+6x3=-5
-2x1+3x2 = 1
x1+x2+7x3=-6
The system of equations can be written as a matrix equation of the form AX=B, where:
A = [1 -2 6; -2 3 0; 1 1 7]
X = [x1; x2; x3]
B = [-5; 1; -6]