3(x-1)(x+1)=9

Solution for 3(x-1)(x+1)=9 equation:

Simplifying
3(x + -1)(x + 1) = 9

Reorder the terms:
3(-1 + x)(x + 1) = 9

Reorder the terms:
3(-1 + x)(1 + x) = 9

Multiply (-1 + x) * (1 + x)
3(-1(1 + x) + x(1 + x)) = 9
3((1 * -1 + x * -1) + x(1 + x)) = 9
3((-1 + -1x) + x(1 + x)) = 9
3(-1 + -1x + (1 * x + x * x)) = 9
3(-1 + -1x + (1x + x2)) = 9

Combine like terms: -1x + 1x = 0
3(-1 + 0 + x2) = 9
3(-1 + x2) = 9
(-1 * 3 + x2 * 3) = 9
(-3 + 3x2) = 9

Solving
-3 + 3x2 = 9

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '3' to each side of the equation.
-3 + 3 + 3x2 = 9 + 3

Combine like terms: -3 + 3 = 0
0 + 3x2 = 9 + 3
3x2 = 9 + 3

Combine like terms: 9 + 3 = 12
3x2 = 12

Divide each side by '3'.
x2 = 4

Simplifying
x2 = 4

Take the square root of each side:
x = {-2, 2}