A. (2,-5)
This point is NOT a solution since this point does not satisfy the second equation: 2x - y = 6, as 2x-y = 2(2)-(-5) = 4+5 = 9
B. (1,-4)
This point is INDEED a solution since this point satisfies both the equations:
first equation: x+y = 1-4 = -5
first equation: 2x - y = 2(1)-(-4) = 2+4 = 6
