3x^2-1=28

Solution for 3x^2-1=28 equation:

Simplifying
3x2 + -1 = 28

Reorder the terms:
-1 + 3x2 = 28

Solving
-1 + 3x2 = 28

Solving for variable 'x'.

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

Add '1' to each side of the equation.
-1 + 1 + 3x2 = 28 + 1

Combine like terms: -1 + 1 = 0
0 + 3x2 = 28 + 1
3x2 = 28 + 1

Combine like terms: 28 + 1 = 29
3x2 = 29

Divide each side by '3'.
x2 = 9.666666667

Simplifying
x2 = 9.666666667

Take the square root of each side:
x = {-3.109126351, 3.109126351}