(25(x^2)-81)=0

Solution for (25(x^2)-81)=0 equation:

Simplifying
(25(x2) + -81) = 0

Reorder the terms:
(-81 + 25x2) = 0

Remove parenthesis around (-81 + 25x2)
-81 + 25x2 = 0

Solving
-81 + 25x2 = 0

Solving for variable 'x'.

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

Add '81' to each side of the equation.
-81 + 81 + 25x2 = 0 + 81

Combine like terms: -81 + 81 = 0
0 + 25x2 = 0 + 81
25x2 = 0 + 81

Combine like terms: 0 + 81 = 81
25x2 = 81

Divide each side by '25'.
x2 = 3.24

Simplifying
x2 = 3.24

Take the square root of each side:
x = {-1.8, 1.8}