86.4+0.5*4.25*x^2=329

Solution for 86.4+0.5*4.25*x^2=329 equation:

Simplifying
86.4 + 0.5 * 4.25x2 = 329

Multiply 0.5 * 4.25
86.4 + 2.125x2 = 329

Solving
86.4 + 2.125x2 = 329

Solving for variable 'x'.

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

Add '-86.4' to each side of the equation.
86.4 + -86.4 + 2.125x2 = 329 + -86.4

Combine like terms: 86.4 + -86.4 = 0.0
0.0 + 2.125x2 = 329 + -86.4
2.125x2 = 329 + -86.4

Combine like terms: 329 + -86.4 = 242.6
2.125x2 = 242.6

Divide each side by '2.125'.
x2 = 114.1647059

Simplifying
x2 = 114.1647059

Take the square root of each side:
x = {-10.684788529, 10.684788529}