Domain: (-∞, ∞)
Range: [3, ∞)
Domain Explanation:
Domain is the x-axis, which you can see has both arrows pointing horizontally, so we can tell it is infinite, which means it will be (-∞, ∞) or negative infinity, positive infinity.
Range Explanation:
Range is the y-axis, or the vertical plane which we can see only starts at 3, then go infinitely. This would include 3, so it would be a bracket then a parenthesis. [3, ∞)