40=.5*6*x^2

Solution for 40=.5*6*x^2 equation:

Simplifying
40 = 0.5 * 6x2

Multiply 0.5 * 6
40 = 3x2

Solving
40 = 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.
40 + -3x2 = 3x2 + -3x2

Combine like terms: 3x2 + -3x2 = 0
40 + -3x2 = 0

Add '-40' to each side of the equation.
40 + -40 + -3x2 = 0 + -40

Combine like terms: 40 + -40 = 0
0 + -3x2 = 0 + -40
-3x2 = 0 + -40

Combine like terms: 0 + -40 = -40
-3x2 = -40

Divide each side by '-3'.
x2 = 13.33333333

Simplifying
x2 = 13.33333333

Take the square root of each side:
x = {-3.651483716, 3.651483716}