How do i solve this using elimination? 80x + 45y = 645 x + y = 12

If you combine like terms and do them differently you will have 3 different answers

X + y = 12  / x (-45);
Then, -45x - 45y = -540;
We have 80x + 45y = 645 and
               -45x - 45y = -540
           
                35x           = 105;
Finally, x = 105÷35;
x = 3;
y = 12 - 3;
y = 9;

Thats where they was ported and the fields that noone really knew much about needed tended, so they put slaves out there do free work and huge profits and so on the north decided to hold its own and was more different way of survival did not have same climate conditions to afford protecting slaves from winter so expenses be diff from south