Which systems of equations have no solutions? (Check all that apply.)

In A, multiplying x − y = 1 by −3 gives −3x + 3y = −3, but the other equation says −3x + 3y = 3. The same expression cannot equal both numbers, so A has no solution. In D, the first equation is equivalent to 3x + y = −5, while the second is equivalent to 3x + y = 2; these are also inconsistent, so D has no solution.

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