Question

x menos Y igual a 16 e x mais y igual 74

Answer 1

  x - y = 16
  x + y = 74
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2x = 90
  x = 90/2
  x = 45


x + y = 74
45 + y = 74
   y = 74 - 45
   y = 29              S = {(45, 29)}