Answer:
Second Graph.
Explanation:
It's the only graph that is concave down and the slope is decreasing.
You need to isolate the variables. For the first equation add x to both sides, which leaves you with y.
For the second equation, divide each side by 2 leaving you with
x= 6+y. Subtract y from each side. Subtract x from both sides. Now you have y= x + 6.
Now graph those equations.
The answer is the first one