25k^2-81=0

Solution for 25k^2-81=0 equation:

Simplifying
25k2 + -81 = 0

Reorder the terms:
-81 + 25k2 = 0

Solving
-81 + 25k2 = 0

Solving for variable 'k'.

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

Add '81' to each side of the equation.
-81 + 81 + 25k2 = 0 + 81

Combine like terms: -81 + 81 = 0
0 + 25k2 = 0 + 81
25k2 = 0 + 81

Combine like terms: 0 + 81 = 81
25k2 = 81

Divide each side by '25'.
k2 = 3.24

Simplifying
k2 = 3.24

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