2[x+3(x-1)]=42

Solution for 2[x+3(x-1)]=42 equation:

Simplifying
2[x + 3(x + -1)] = 42

Reorder the terms:
2[x + 3(-1 + x)] = 42
2[x + (-1 * 3 + x * 3)] = 42
2[x + (-3 + 3x)] = 42

Reorder the terms:
2[-3 + x + 3x] = 42

Combine like terms: x + 3x = 4x
2[-3 + 4x] = 42
[-3 * 2 + 4x * 2] = 42
[-6 + 8x] = 42

Solving
-6 + 8x = 42

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 + 8x = 42 + 6

Combine like terms: -6 + 6 = 0
0 + 8x = 42 + 6
8x = 42 + 6

Combine like terms: 42 + 6 = 48
8x = 48

Divide each side by '8'.
x = 6

Simplifying
x = 6