3(2x^2-4)=42

Solution for 3(2x^2-4)=42 equation:

Simplifying
3(2x2 + -4) = 42

Reorder the terms:
3(-4 + 2x2) = 42
(-4 * 3 + 2x2 * 3) = 42
(-12 + 6x2) = 42

Solving
-12 + 6x2 = 42

Solving for variable 'x'.

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

Add '12' to each side of the equation.
-12 + 12 + 6x2 = 42 + 12

Combine like terms: -12 + 12 = 0
0 + 6x2 = 42 + 12
6x2 = 42 + 12

Combine like terms: 42 + 12 = 54
6x2 = 54

Divide each side by '6'.
x2 = 9

Simplifying
x2 = 9

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