Returning different values when comparing 2 cells

I need an if statement for 3 different scenario's :

Cell A1 = value a
Cell A2 = value b

Scenario 1
Cell A3 = where cell A1 is greater than A2 the value in cell A3 = x

Scenario 2
Cell A3 = where cell A1 is equal to A2 the value in cell A3 = y

Scenario 3
Cell A3 = where cell A1 is less than A2 the value in cell A3 = z