Question

Which of the following equations have exactly one solution?
Choose all answers that apply:
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A) 6x – 6 = 15x + 15
B) 6x – 15 = 6x +15
C) 6x – 6 = 6x + 15
D) 6x + 15 = 6x + 15

Answer 1

$A) 6x-6=15x+15\\9x=-9\\x=-1\\\\B) 6x-15=6x+15\\0x=30$

the equation has no solutions

$C) 6x-6=6x+15\\0x=21$

the equation has no solutions

$D) 6x+15=6x+15\\0x=0$

x∈(-∞;+∞)

Answer: Only A has only 1 solution

P.S. Hello from Russia