9x^2-40=0

Solution for 9x^2-40=0 equation:

Simplifying
9x2 + -40 = 0

Reorder the terms:
-40 + 9x2 = 0

Solving
-40 + 9x2 = 0

Solving for variable 'x'.

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

Add '40' to each side of the equation.
-40 + 40 + 9x2 = 0 + 40

Combine like terms: -40 + 40 = 0
0 + 9x2 = 0 + 40
9x2 = 0 + 40

Combine like terms: 0 + 40 = 40
9x2 = 40

Divide each side by '9'.
x2 = 4.444444444

Simplifying
x2 = 4.444444444

Take the square root of each side:
x = {-2.108185107, 2.108185107}