Final answer:
The correct representation of the set of all numbers greater than or equal to −6 in interval notation is [−6, ∞), which is answer D.
Step-by-step explanation:
The student is asking about interval notation, which is a way of representing subsets of the real number line. In this notation, parentheses ( ) indicate that the endpoint is not included in the set, while brackets [ ] indicate that the endpoint is included. The student wants to know the correct representation for the set of all numbers greater than or equal to −6.
The correct answer is D) [−6, ∞). This represents all real numbers starting from −6, including −6 itself (hence the bracket [), and extending to infinity (note that infinity always gets a parenthesis because we can never reach infinity).
Option A is incorrect because it includes numbers less than −6. Option B is the set of all real numbers, and option C is the set of numbers greater than −6 but not including −6 itself, due to the parenthesis.