[tex]6x-4y=54\qquad\text{subtract 6x from both sides}\\\\-4y=-6x+54\qquad\text{divide both sides by (-2)}\\\\2y=3x-27\\\\\text{Substitute it to the second equation}\ -9x+2y=-69:\\\\-9x+(3x-27)=-69\\\\-9x+3x-27=-69\qquad\text{add 27 to both sides}\\\\-6x=-42\qquad\text{divide both sides by (-6)}\\\\\boxed{x=7}\\\\\text{Put the value of x to the equation}\ 2y=3x-27:\\\\2y=3(7)-27\\\\2y=21-27\\\\2y=-6\qquad\text{divide both sides by 2}\\\\\boxed{y=-3}\\\\Answer:\ \boxed{x=7\ and\ y=-3\to(7,\ -3)}[/tex]
