In solving linear eqution br elimination, 2x+y=4x+y=-2?

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x=0
y=-2

Not clear.
Is it
(i)
2x + y = 4
x + y = - 2

OR

(ii)
2x + y = - 2
4x + y = - 2

Try (i) :-
2x + y = 4
- x - y = 2-----ADD

x = 6

12 + y = 4
y = - 8

x = 6 , y = -8

2x + y = 4
x + y = -2

x + y = -2
2(x + y) = 2(-2)
2x + 2y = -4

...2x + y = 4
--2x + 2y = -4
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-y = 8

-y = 8
y = 8/-1
y = -8

2x + y = 4
2x + (-8) = 4
2x - 8 = 4
2x = 4 + 8
2x = 12
x = 12/2
x = 6

∴ x = 6 , y = -8

4x + y = -2
2x + y = -2 ........ subtract
2x = 0
x = 0
y = -2

Assuming you have written the equations correctly:

2x + y = 4x + y so therefore 2x = 4x and the only way that can happen is if x = 0

so y = -2