X ^ 2-9x + 20 = 0

X ^ 2-9x + 20 = 0

  • X-9x + 20 = 0
    D = 81-80 = 1
    x = (9 + 1): 2 = 5
    x = (9-1): 2 = 4
  • X (x-9) = 0
    x1 = 0 або х-9 = 0
    х2 = 9