[3x(x)]+4=16

Solution for [3x(x)]+4=16 equation:

Simplifying
[3x(x)] + 4 = 16

Multiply x * x
[3x2] + 4 = 16

Reorder the terms:
4 + [3x2] = 16

Solving
4 + [3x2] = 16

Solving for variable 'x'.

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

Add '-4' to each side of the equation.
4 + -4 + [3x2] = 16 + -4

Combine like terms: 4 + -4 = 0
0 + [3x2] = 16 + -4
[3x2] = 16 + -4

Combine like terms: 16 + -4 = 12
[3x2] = 12

Divide each side by '3'.
x2 = 4

Simplifying
x2 = 4

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