3(x^2-2)=18

Solution for 3(x^2-2)=18 equation:

Simplifying
3(x2 + -2) = 18

Reorder the terms:
3(-2 + x2) = 18
(-2 * 3 + x2 * 3) = 18
(-6 + 3x2) = 18

Solving
-6 + 3x2 = 18

Solving for variable 'x'.

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

Add '6' to each side of the equation.
-6 + 6 + 3x2 = 18 + 6

Combine like terms: -6 + 6 = 0
0 + 3x2 = 18 + 6
3x2 = 18 + 6

Combine like terms: 18 + 6 = 24
3x2 = 24

Divide each side by '3'.
x2 = 8

Simplifying
x2 = 8

Take the square root of each side:
x = {-2.828427125, 2.828427125}