Question

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

Answer 1

Answer:

x = -2 or x = 2

Step-by-step explanation:

$x^2-4=0\qquad\text{add 4 to both sides}\\\\x^2-4+4=0+4\\\\x^2=4\iff\sqrt{x^2}=\sqrt4\\\\|x|=2\Rightarrow x=\pm2$

Answer 2

Answer:

For $x^2 - 4 = 0$, x  = 2, or x = - 2.

Step-by-step explanation:

Here, the given expression is :

$x^2 - 4 = 0$

Now, using the ALGEBRAIC IDENTITY:

$a^2 - b^2 = (a-b)(a+b)$

Comparing this with the above expression, we get

$x^2 - 4 = 0 = x^2 - (2)^2 = 0\\\implies (x-2)(x+2) = 0$

⇒Either (x-2) = 0 , or ( x + 2) = 0

So, if ( x- 2)   = 0 ⇒ x =  2

and if ( x + 2) = 0   ⇒ x = -2

Hence, for $x^2 - 4 = 0$, x  = 2, or x = - 2.