(3x-9)(x+3)=0

Solution for (3x-9)(x+3)=0 equation:

Simplifying
(3x + -9)(x + 3) = 0

Reorder the terms:
(-9 + 3x)(x + 3) = 0

Reorder the terms:
(-9 + 3x)(3 + x) = 0

Multiply (-9 + 3x) * (3 + x)
(-9(3 + x) + 3x * (3 + x)) = 0
((3 * -9 + x * -9) + 3x * (3 + x)) = 0
((-27 + -9x) + 3x * (3 + x)) = 0
(-27 + -9x + (3 * 3x + x * 3x)) = 0
(-27 + -9x + (9x + 3x2)) = 0

Combine like terms: -9x + 9x = 0
(-27 + 0 + 3x2) = 0
(-27 + 3x2) = 0

Solving
-27 + 3x2 = 0

Solving for variable 'x'.

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

Add '27' to each side of the equation.
-27 + 27 + 3x2 = 0 + 27

Combine like terms: -27 + 27 = 0
0 + 3x2 = 0 + 27
3x2 = 0 + 27

Combine like terms: 0 + 27 = 27
3x2 = 27

Divide each side by '3'.
x2 = 9

Simplifying
x2 = 9

Take the square root of each side:
x = {-3, 3}