(x^2+9)-90=0

Solution for (x^2+9)-90=0 equation:

Simplifying
(x2 + 9) + -90 = 0

Reorder the terms:
(9 + x2) + -90 = 0

Remove parenthesis around (9 + x2)
9 + x2 + -90 = 0

Reorder the terms:
9 + -90 + x2 = 0

Combine like terms: 9 + -90 = -81
-81 + x2 = 0

Solving
-81 + x2 = 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 + x2 = 0 + 81

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

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

Simplifying
x2 = 81

Take the square root of each side:
x = {-9, 9}