First, add #color(red)(1.8)# to each side of the equation to isolate the #y# term while keeping the equation balanced:
#3.2y - 1.8 + color(red)(1.8) = 3 + color(red)(1.8)#
#3.2y - 0 = 4.8#
#3.2y = 4.8#
Now, divide each side of the equation by #color(red)(3.2)# to solve for #y# while keeping the equation balanced:
#(3.2y)/color(red)(3.2) = 4.8/color(red)(3.2)#
#(color(red)(cancel(color(black)(3.2)))y)/cancel(color(red)(3.2)) = (1.6 xx 3)/color(red)(1.6 xx 2)#
#y = (color(red)(cancel(color(black)(1.6))) xx 3)/color(red)(color(black)(cancel(color(red)(1.6))) xx 2)#
#y = 3/color(red)(2)#
#y = 1.5#