Step-by-step explanation: Domain is the range of possible x values that make sense in the equation. Since the x values are time, and there cannot be negative time, x must obviously be positive. And since y is height and height can't be negative, the domain of x ends at the x-intercept, the point at which y begins to become negative. So the domain of x is 0 is less than or equal to x which is less than or equal to about 4.75.
