Choose a system of equations with the same solution as the following system:

6x + 2y = −6
3x − 4y = −18

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A: 8x + 4y = −4
17x + 2y = −28

B: 12x + 4y = 12
21x + 2y = −36

C: 6x + 8y = −36
15x + 6y = −60

D: 6x + y = 15
15x − y = −9