2x^2-9=x^2

Solution for 2x^2-9=x^2 equation:

Simplifying
2x2 + -9 = x2

Reorder the terms:
-9 + 2x2 = x2

Solving
-9 + 2x2 = x2

Solving for variable 'x'.

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

Add '-1x2' to each side of the equation.
-9 + 2x2 + -1x2 = x2 + -1x2

Combine like terms: 2x2 + -1x2 = 1x2
-9 + 1x2 = x2 + -1x2

Combine like terms: x2 + -1x2 = 0
-9 + 1x2 = 0

Add '9' to each side of the equation.
-9 + 9 + 1x2 = 0 + 9

Combine like terms: -9 + 9 = 0
0 + 1x2 = 0 + 9
1x2 = 0 + 9

Combine like terms: 0 + 9 = 9
1x2 = 9

Divide each side by '1'.
x2 = 9

Simplifying
x2 = 9

Take the square root of each side:
x = {-3, 3}