X^2 - 3X = 0
X * ( X - 3 ) = 0
X = 0
X - 3 = 0 ---> X = 3
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1) X^2 - 3X + 12K = 0
0 ^2 - 3 * 0 + 12K = 0
12K = 0
K = 0
2) X^2 - 3X + 12K = 0
3 ^2 - 3 * 3 + 12K = 0
12K = 0
K = 0
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ОТВЕТ: при К = 0