2a^2-81=0

Solution for 2a^2-81=0 equation:

Simplifying
2a2 + -81 = 0

Reorder the terms:
-81 + 2a2 = 0

Solving
-81 + 2a2 = 0

Solving for variable 'a'.

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

Add '81' to each side of the equation.
-81 + 81 + 2a2 = 0 + 81

Combine like terms: -81 + 81 = 0
0 + 2a2 = 0 + 81
2a2 = 0 + 81

Combine like terms: 0 + 81 = 81
2a2 = 81

Divide each side by '2'.
a2 = 40.5

Simplifying
a2 = 40.5

Take the square root of each side:
a = {-6.363961031, 6.363961031}