The second option you listed: x + y = 4 gives the same line as H, and therefore renders infinite number of solutions (as many as every point on the line)
Step-by-step explanation:
We need to look for the equation that exactly matches the given one :
2 x + 2 y = 8
notice dividing both sides of this equation by "2" we get:
x + y = 4
SO this equation represents exactly the same line as 2 x + 2 y = 8 does, and therefore their graphs overlap completely