Trying to Run Solver multiple times

I am trying to create a code that will allow me to run solver multiple times. I am trying to solve a duopoly question that by changing the quantities of Firm 1 & Firm 2 it will create the maximum condition. The quantities of both firms should be the same. The answer is 80 for both firms, now i just need to find a code that will get me that answer. I am going to include the excel spreadsheet so that you may see what I am trying to find out. I am new to VBA and I have no idea what to do. Any help would be appreciated. Thanks!