2х+1/8,1=2/1,8 решите уравнения

[latex] \frac{(2+1)}{1,8} = \frac{2}{1,8} \\ \frac{20x+10}{81} = \frac{10}{9} \\ 20x+10= \frac{10*81}{9} \\ 20x=90-10 \\ x=80/20 \\ x=4[/latex]