[tex]\dfrac{5x-2}{40}=\dfrac{6x+6}{55}\ \ \ |cross\ multiply\\\\55(5x-2)=40(6x+6)\\\\275x-110=240x+240\ \ \ |+110\\\\275x=240x+350\ \ \ \ |-240x\\\\35x=350\ \ \ |:35\\\\x=10[/tex]
