Answer:
y=0.75x+300
Explanation:
So for this problem, I'm going to put it in slope-intercept form (only because it makes the most sense to me, plus if you need to graph it, this will be helpful)
So Jan is donating $300 first. So whatever you need to do, you need to add 300 afterwards to account for that donation. But then, Jan is going to donate $0.75 for every large coffee ordered. This is means it is a dependent variable. The amount is dependent on how many large coffees ordered.
Say, for example, there were 15 large coffees ordered. You should multiply 0.75*15, which will give you a product of 11.25. So for all the coffees ordered, Jan will donate a total of $11.25 (which isn't a lot, but that's okay). But that isn't ALL the money that Jan donated because, as stated before, Jan is going to donate $300 regardless of how many coffees ordered. So the total amount of money donated is $311.25
Hope this helps!