Respuesta :

(x + 2) (x - 18) = 0
x + 2 = 0 or x - 18 = 0
x = -2 or x = 18

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Answer: x = -2 or x = 18
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Either one at any given time could be equal to zero. So
x + 2 = 0
x = - 2

x - 18 = 0
x = 18

I've enclosed a graph of this so you can see that the answers I've given are the ones expected.
Ver imagen jcherry99
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