Solve the system below and tell whether it has one solution, Infinitely many solutions or No solution. x+y=-2

Question

-x-y=4

Answer 1

without attempting to solve, notice that the 2nd equation can be written as
x + y = -4
compare that with x + y = -2, it is obvious that, since they have the same
slope but different y-intercepts,
we are looking at two parallel lines, which of course will never intersect

So what do you think?