(2x^2-20)-289=0

Solution for (2x^2-20)-289=0 equation:

Simplifying
(2x2 + -20) + -289 = 0

Reorder the terms:
(-20 + 2x2) + -289 = 0

Remove parenthesis around (-20 + 2x2)
-20 + 2x2 + -289 = 0

Reorder the terms:
-20 + -289 + 2x2 = 0

Combine like terms: -20 + -289 = -309
-309 + 2x2 = 0

Solving
-309 + 2x2 = 0

Solving for variable 'x'.

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

Add '309' to each side of the equation.
-309 + 309 + 2x2 = 0 + 309

Combine like terms: -309 + 309 = 0
0 + 2x2 = 0 + 309
2x2 = 0 + 309

Combine like terms: 0 + 309 = 309
2x2 = 309

Divide each side by '2'.
x2 = 154.5

Simplifying
x2 = 154.5

Take the square root of each side:
x = {-12.429802895, 12.429802895}