If, show that x = f(y).
Given
We need to prove that x = f(y).
We have
⇒ y(bx – a) = ax – b
⇒ bxy – ay = ax – b
⇒ bxy – ax = ay – b
⇒ x(by – a) = ay – b
∴ x = f(y)
Thus, x = f(y).