x^2+(x^2-4)=20

Solution for x^2+(x^2-4)=20 equation:

Simplifying
x2 + (x2 + -4) = 20

Reorder the terms:
x2 + (-4 + x2) = 20

Remove parenthesis around (-4 + x2)
x2 + -4 + x2 = 20

Reorder the terms:
-4 + x2 + x2 = 20

Combine like terms: x2 + x2 = 2x2
-4 + 2x2 = 20

Solving
-4 + 2x2 = 20

Solving for variable 'x'.

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

Add '4' to each side of the equation.
-4 + 4 + 2x2 = 20 + 4

Combine like terms: -4 + 4 = 0
0 + 2x2 = 20 + 4
2x2 = 20 + 4

Combine like terms: 20 + 4 = 24
2x2 = 24

Divide each side by '2'.
x2 = 12

Simplifying
x2 = 12

Take the square root of each side:
x = {-3.464101615, 3.464101615}