Question 182497
Check out this <a href="http://www.freewebs.com/jimthompson5910/rref%20solution.htm">link</a> to see the solution which was generated by the <a href="http://www.math.odu.edu/~bogacki/lat/">Linear Algebra Toolkit</a>


Notice how the right hand column of the last step has the values (from top to bottom): 7, 2, 3, -1


So this tells us that the solutions are


{{{a=7}}}, {{{b=2}}}, {{{c=3}}}, and {{{d=-1}}}