You would use 539 and square it on you cal. just once. Then once you do that the answer is not going to be a whole number it is going to have a decimal, so the answer would be 23.22.
The answer for the question is C
Use elimination
-x - y = -9
x - y = 3
Add both equations
-2y = -6, y = 3
-x -(3) = -9
-x = -6, x = 6
Final answer: x = 6, y = 3
