Answer:
X = - 2 or X = 2
Step-by-step explanation:
*completing the square*
X^2 - 4 = 0
X^2 = 4
X = +-√4
x = +-2
x= -2, 2
*factoring*
X^2 - 4 = 0
(x-2)(x+2) = 0
|. |
x = 2, x = -2
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(x-2)(x+2) = x(x+2) - 2(x+2) = x^2 + 2x - 2x - 4 = x^2-4
