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用加减法解方程组\(\left\{ {\begin{array}{*{20}{l}} {5x + y = 4(1)} \\ {7x + 2y = - 9(2)} \end{array}} \right.\)时,(1)\( \times 2 - \)(2)得\((\) \()\)
A.\(3x = - 1\)
B.\( - 2x = 13\)
C.\(17x = - 1\)
D.\(3x = 17\)
参考答案:D
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