Note that #0.4 ->4/10# and that #+(-2)->-2#
Write as #4/10(2x+1/2) = 3(0.2x-2)#
Getting rid of the 10 from #4/10# multiply both sides by 10
#4(2x+1/2)=30(color(white)(".")0.2x-2color(white)("."))#
Changing the #0.2# in the right bracket to #2/10#
#4(2x+1/2)=30(color(white)(".")2/10x-2color(white)("."))#
Multiply everything inside the bracket by what is outside
#8x+2color(white)("dd")=color(white)("dd")6x-60#
Subtract #color(red)(6x)# from both sides
#color(green)(8xcolor(red)(-6x)+2color(white)("dd")=color(white)("dd")6xcolor(red)(-6x)-60)#
#color(white)("dd")2xcolor(white)(".d")+2color(white)("dd")=color(white)("dddd")0color(white)("d.d")-60#
Subtract 2 from both sides
#2xcolor(white)("d")=color(white)("d")-62#
Divide both sides by 2
#color(green)(2/color(red)(2) x color(white)("d")=color(white)("d")-62/color(red)(2))#
#x=-31#