The X (1) axis represents the number of hours, and the Y (75) axis represents the number of dollars. When 0 hours are passed, 0 hours are payed (0,0) 1 hour 75 dollars are payed (1, 75) 2 hours 150 dollars is payed (2, 150) and so on
Answer:
The solution is 1.
Step-by-step explanation:
Logarithm:
Suppose we have a logarithmic equation in the following format:

It means that:

In this question:

Which means that:

Every number, elevated to 0, is 1. So

Which means that the solution is 
Let 0.25x is the price increase. Therefore, the number of attendees will be 350-10x and the revenue R=(350-10x)*(5+0.25x)=1750+37.5x-2.5x^2. This parabola has maximum at x=10, meaning the price=7.5
Yi forgot two factors of 63, which are 3 and 21.
This would make the greatest common factor 21.