Here's a math problem. I hope you can solve it It is known that a is a real number. For the binary linear equations of X, y, 2x-3y = 5A and X + 2Y = 1-2a, the solution of this system is impossible 1. X, y are all positive numbers 2. X, y are all negative numbers 3. X are positive numbers, y are negative numbers 4. X are negative numbers, y are positive numbers

2x-3y = 5a, ① x + 2Y = 1-2a, ② X2 - ①, 7Y = 2-9a, y = (2-9a) / 7
X = (3 + 4a) / 7 seems to be true, when 2 / 9 > a > - 3 / 4, (1) holds, when A2 / 9, (3) holds, only (2) does not hold
Give me the ticket, landlord, for the sake of all I've written, and I'll do the task. Thank you

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