Idk what linear combination is but you can solve this way:
3x+y=4
-2x-y=-5
x=-1
3(-1)+y=4
-3+y=4
y=7
So x=-1 and y=7
It is likely D I am not positive
You have to subtract the degrees like in this picture:
Answer:
The area of building c minus the area of building b equals the area of building a might be correct?
