Final answer:
The statement x + y ∈ ℝ is true based on the Closure property for addition, which states that when two real numbers are added, the sum is also a real number.
Step-by-step explanation:
The statement x + y ∈ ℝ is true based on the Closure property for addition.
Closure property states that when two real numbers are added, the sum is also a real number. In other words, if x and y are real numbers, then x + y will also be a real number.
For example, if x = 2 and y = 3, then x + y = 2 + 3 = 5, which is a real number.