3x^2-1=20

Solution for 3x^2-1=20 equation:

Simplifying
3x2 + -1 = 20

Reorder the terms:
-1 + 3x2 = 20

Solving
-1 + 3x2 = 20

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 = 20 + 1

Combine like terms: -1 + 1 = 0
0 + 3x2 = 20 + 1
3x2 = 20 + 1

Combine like terms: 20 + 1 = 21
3x2 = 21

Divide each side by '3'.
x2 = 7

Simplifying
x2 = 7

Take the square root of each side:
x = {-2.645751311, 2.645751311}