[tex]A) 6x-6=15x+15\\9x=-9\\x=-1\\\\B) 6x-15=6x+15\\0x=30\\[/tex]
the equation has no solutions
[tex]C) 6x-6=6x+15\\0x=21[/tex]
the equation has no solutions
[tex]D) 6x+15=6x+15\\0x=0[/tex]
x∈(-∞;+∞)
Answer: Only A has only 1 solution
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