What is the slope of the line x = 4?

Mathematically and line graph math the y needs to be permanent and the x always changes that is why all them start with y=, so I think the slope in this case doesnt exist, and by the way it will look like a vertical line, not horizontal.

the red lines denote the population of the bacteria after 35 hours. that would be 2,409.24. the y-intercept is the blue line which is 800 because that is the starting point. the equation used to make the graph is 800(1.032)^h, where h is the number of hours.

step-by-step explanation: