81x^2-243=0

Solution for 81x^2-243=0 equation:

Simplifying
81x2 + -243 = 0

Reorder the terms:
-243 + 81x2 = 0

Solving
-243 + 81x2 = 0

Solving for variable 'x'.

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

Add '243' to each side of the equation.
-243 + 243 + 81x2 = 0 + 243

Combine like terms: -243 + 243 = 0
0 + 81x2 = 0 + 243
81x2 = 0 + 243

Combine like terms: 0 + 243 = 243
81x2 = 243

Divide each side by '81'.
x2 = 3

Simplifying
x2 = 3

Take the square root of each side:
x = {-1.732050808, 1.732050808}