Answer:
C since its including a wider range of people that arent limited to friends or a certain sports team
Answer:
x+y=30
2x+3y=80
multiplying equation one by -3 and add equation
-3x -3y=-90
2x +3y=80
2(10)+20(3)=80
80=80
I'm not sure how you obtained -5 as your answer but this is the mathematical explanation. hope this helps!