At a club meeting, there are 10 more club members than nonmembers. the number of club members at the meeting is c. which one is greater or are they equal? a. the total number of people at the club meeting b. 2c-10

A. To know the exact number of number of people at the meeting you need to know at least one variable either the number of non club members or the number of people who attended the club meeting. 
Without these you will not be able to solve the problem 

B. The number of club members who attend the meeting will always have 10 more people so they will be the greater number people against nonmembers