Maxima: Transforming solutions obtained by linsolve.

I am using linsolve() for the solution of linear equations.  For example:


(%i513) ysol : linsolve([a11*x1+a12*x2+a13*x3],[x1,x2,x3]);

(%o513) [x1 = -(%r1*a13+%r2*a12)/a11,x2 = %r2,x3 = %r1]
(%i514)

I want to transform the obtained solution to the following form:

xsol = A . r

where r = matrix([%r1],[%r2])

and A = matrix([-a13/a11,-a12/a11],[0,1],[1,0])

Its not clear how to construct or extract the matrix A (and the matrix r) 
from the list ysol. 

I could not extract the %r1 and %r2  as these seem to be different each time 
linsolve() is called, eg %r3, %r4, etc

Any assistance would be appreciated.

TIA

C. Frangos.