Answer:
x = 18
Step-by-step explanation:
[tex]12-\dfrac{2}{3}x=x-18\qquad\text{subtract 12 from both sides}\\\\12-12-\dfrac{2}{3}x=x-18-12\\\\-\dfrac{2}{3}x=x-30\qquad\text{multiply both sides by 3}\\\\3\!\!\!\!\diagup\cdot\left(-\dfrac{2}{3\!\!\!\!\diagup_1}x\right)=3\cdot x-3\cdot30\\\\-2x=3x-90\qquad\text{subtract}\ 3x\ \text{from both sides}\\\\-2x-3x=3x-3x-90\\\\-5x=-90\qquad\text{divide both sides by (-5)}\\\\\dfrac{-5x}{-5}=\dfrac{-90}{-5}\\\\x=18[/tex]
