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

/* code_begins */

{{{
A=matrix([[1,1,2],[2,3,-1],[3,4,1]])
x,y,z=var('u,v,w')
x=matrix([[u],[v],[w]])
c=var('c')
b=matrix([[2],[5],[c]])
A.rank()
Aug=matrix([[1,1,2,2],[2,3,-1,5],[3,4,1,c]])
Aug.rescale_row(1,-1)
Aug.add_multiple_of_row(1,0,2)
Aug.rescale_row(2,-1)
Aug.add_multiple_of_row(2,0,3)
Aug.rescale_row(1,-1)
Aug.add_multiple_of_row(2,1,1)
Aug[2,3]=0
solve(-c+7==0,c)
}}}

/* code_ends */

 * '''Solution by''': 
   * <Monica>, <Student>, <SNIST>