disp('performing Gaussian elimination')
a=[1 5;-2 -7]
disp('the co-efficient matrix is:')
disp(a)
b=[7;-5]
c=[a b]
disp('the augmented matrix is:')
disp(c)
disp('R2=R2+2*R1')
c(2,:)=c(2,:)+2*c(1,:)
disp(c)
disp('R2=(1/3)*R2')
c(2,:)=(1/3)*c(2,:)
disp(c)
disp('R1=R1-5*R2')
c(1,:)=c(1,:)-5*c(2,:)
disp(c)
x1=c(1,3)/c(1,1)
x2=c(2,3)/c(2,2)
printf('the solution is:x1=%d x2=%d',x1,x2)