The water of a tank is initially 24 feet, and it is being
drained at a rate of 3 feet per day. The equation below
expresses the water level, y, in feet, in terms of the number
of days, x, since the tank began draining.
y = 24 - 3x
A scientist might be interested in the x-intercept of this
equation because it represents the moment when the tank
will be empty. Which of the following is the x-intercept of
the equation above?