First, group and combine like terms on the left side of the equation:
#4x + 2x + 4 = 20#
#(4 + 2)x + 4 = 20#
#6x + 4 = 20#
Next, subtract #color(red)(4)# from each side of the equation to isolate the #x# term while keeping the equation balanced:
#6x + 4 - color(red)(4) = 20 - color(red)(4)#
#6x + 0 = 16#
#6x = 16#
Now, divide each side of the equation by #color(red)(6)# to solve for #x# while keeping the equation balanced:
#(6x)/color(red)(6) = 16/color(red)(6)#
#(color(red)(cancel(color(balck)(6)))x)/cancel(color(red)(6)) = (2 xx 8)/color(red)(2 xx 3)#
#x = (color(red)(cancel(color(black)(2))) xx 8)/color(red)(color(black)(cancel(color(red)(2))) xx 3)#
#x = 8/3#
