I think the answer is B
There are 3500 students in the freshman class.
Answer:
adding both equations
4x+9y=5
-4x+7y=11
+ + =+
________
0 +16y=16
y=1
putting the value of y in first eqn
4x+9×1=5
4x=5-9
4x=-4
x=-1
so the x is -1 and y is 1