100=x^2+2x^2

Solution for 100=x^2+2x^2 equation:

Simplifying
100 = x2 + 2x2

Combine like terms: x2 + 2x2 = 3x2
100 = 3x2

Solving
100 = 3x2

Solving for variable 'x'.

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

Add '-3x2' to each side of the equation.
100 + -3x2 = 3x2 + -3x2

Combine like terms: 3x2 + -3x2 = 0
100 + -3x2 = 0

Add '-100' to each side of the equation.
100 + -100 + -3x2 = 0 + -100

Combine like terms: 100 + -100 = 0
0 + -3x2 = 0 + -100
-3x2 = 0 + -100

Combine like terms: 0 + -100 = -100
-3x2 = -100

Divide each side by '-3'.
x2 = 33.33333333

Simplifying
x2 = 33.33333333

Take the square root of each side:
x = {-5.773502692, 5.773502692}