Answer:
[tex]\large\boxed{x=\dfrac{51-4y}{7}}[/tex]
Step-by-step explanation:
[tex]7x-4+4y+8=24+31\qquad\text{combine like terms}\\\\7x+4y+(-4+8)=(24+31)\\\\7x+4y+4=55\qquad\text{subtract 4 from both sides}\\\\7x+4y=51\qquad\text{subtract 4y from both sides}\\\\7x=51-4y\qquad\text{divide both sides by 7}\\\\x=\dfrac{51-4y}{7}[/tex]
