13x^2-(10x^2+9)=0

Solution for 13x^2-(10x^2+9)=0 equation:

Simplifying
13x2 + -1(10x2 + 9) = 0

Reorder the terms:
13x2 + -1(9 + 10x2) = 0
13x2 + (9 * -1 + 10x2 * -1) = 0
13x2 + (-9 + -10x2) = 0

Reorder the terms:
-9 + 13x2 + -10x2 = 0

Combine like terms: 13x2 + -10x2 = 3x2
-9 + 3x2 = 0

Solving
-9 + 3x2 = 0

Solving for variable 'x'.

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

Add '9' to each side of the equation.
-9 + 9 + 3x2 = 0 + 9

Combine like terms: -9 + 9 = 0
0 + 3x2 = 0 + 9
3x2 = 0 + 9

Combine like terms: 0 + 9 = 9
3x2 = 9

Divide each side by '3'.
x2 = 3

Simplifying
x2 = 3

Take the square root of each side:
x = {-1.732050808, 1.732050808}