18,000
just use a calculator bro
40 dollars per 5 students=9 dollars per 1 student
divide both sides by 5.
She is starting at 4000, so that is the y-intercept of the graph. She is descending at 40 feet per minute, so her rate of change or slope is -40. The graph would look like this:
0.097- or it could be 0.10 if you round it