Question 766818
m - 2n = 1.....(1)
2m + n = 22.....(2)
Multiply (2) by 2
m - 2n = 1......(1)
4m + 2n = 44.....(3)
Add (1) + (3)
5m     = 45
 m = 9
Substitute m = 9 into (1)
m - 2n = 1......(1)
9 - 2n = 1
  -2n = 1 - 9
  -2n = -8
    n = 4
m = 9 and n = 4.
Hope this helps.
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