Question

What are the solution(s) of x2-4-0?

X=-4 or X-4
X=-2 or X= 2
X=2
X=4

Answer 1

X = - 2 or X = 2

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