Question 546278
2x = (1-y)/(2-y) 


Multiply both sides by the denominator to remove the fraction.


2x(2 - y) = (1-y)/(2-y) times (2 - y)


2x(2 - y) = 1 - y


4x - 2xy = 1 - y


-2xy + y = -4x + 1


Factor out y on the left side.


y(-2x + 1) = -4x + 1


Finally divide both sides by (-2x + 1).  This will isolate y.


y = (-4x + 1)/(-2x + 1)


Done!