Question 817238
x+y=201
x-y=11

let:x-y=11
      x=11+y

solve for y:

   x+y=201
11+y+y=201
    2y=201-11
  2y/2=190/2
     y=95

solve for x:

   x-y=11
  x-95=11
     x=11+95
     x=106

check:

   x+y=201
106+95=201
   201=201 check


   x-y=11
106-95=11
    11=11 check