Question

(x-4)(x+4)=0
oitavo ano

Answer 1

(x - 4).(x + 4) = 0
x - 4 = 0
x = 4

x + 4 = 0
x = - 4
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ou:

(x - 4).(x + 4) = 0
x² + 4x - 4x - 16 = 0
x² - 16 = 0
x² = 16
x = √16

x = + 4 e x = - 4

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R.: x = 4 e x = - 4