I can't tell if the 'x' in the question is another variable, or the symbol for 'times'.
Here are the answers both ways:
3 times Y = 4w
Divide each side of the equation by 3 :
Y = (4/3) w
3xY = 4w
Divide each side of the equation by 3 :
xY = (4/3) w
Divide each side by 'x' :
Y = (4w) / (3x)