X₂ - 2X₁ + 1 = 0
a) X₂ - 2X₁ - 1 = 0
b) X₂ - 2X₁ + 1 = A(X₁ - 2)
c) X₂ - 2X₁ + 1 = (X₁ - 2)
d) X₂ - 2X₁ + 1 = (X₁ + 2)