First, group and combine like terms on each side of the equation:
#5x + x - 3 = 3x - 2 - 1#
#5x + 1x - 3 = 3x - 2 - 1#
#(5 + 1)x - 3 = 3x + (-2 - 1)#
#6x - 3 = 3x + (-3)#
#6x - 3 = 3x - 3#
Next, add #color(red)(3)# and subtract #color(blue)(3x)# from each side of the equation to isolate the #x# term while keeping the equation balanced:
#-color(blue)(3x) + 6x - 3 + color(red)(3) = -color(blue)(3x) + 3x - 3 + color(red)(3)#
#(-color(blue)(3) + 6)x - 0 = 0 - 0#
#3x = 0#
Now, divide each side of the equation by #color(red)(3)# to solve for #x#:
#(3x)/color(red)(3) = 0/color(red)(3)#
#(color(red)(cancel(color(black)(3)))x)/cancel(color(red)(3)) = 0#
#x = 0#