||'''Book'''|| Linear Algebra ||
 ||'''Author'''|| Gilbert Strang ||
 ||'''Edition'''||  ||

/* code_begins */

{{{
x,y,z=var('x,y,z')
A=matrix(QQ,[[2,3,1],[4,7,5],[0,-2,2]])
print A
print
b = vector([8,20,0])
C = A.augment(b.transpose())
print C
print
C.swap_rows(1,0)
print C
print
C.add_multiple_of_row(1, 0,-1/2)
#C.add_multiple_of_row(1, 2, -2)

print C
print

#C.add_multiple_of_row(0, 2, -3)
C.add_multiple_of_row(2, 1, -4)

print C
print
z = C[2,3]/C[2,2]
y = (C[1,3]-C[1,2]*z)/C[1,1]
x=(C[0,3]-C[0,2]*z-C[0,1]*y)/C[0,0]
print "x=",x,"y=",y,"z=",z
}}}

/* code_ends */

  * '''Solution by''': 
   * RACHIT JHA, STUDENT, IIT ROORKEE
   * AMIT TEWARI, STUDENT, IIT ROORKEE
   * ARNAB BASU, STUDENT, IIT ROORKEE
   * SHUBHAM MITTAL, STUDENT, IIT ROORKEE