231.2=0.8x^2

Solution for 231.2=0.8x^2 equation:

Simplifying
231.2 = 0.8x2

Solving
231.2 = 0.8x2

Solving for variable 'x'.

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

Add '-0.8x2' to each side of the equation.
231.2 + -0.8x2 = 0.8x2 + -0.8x2

Combine like terms: 0.8x2 + -0.8x2 = 0.0
231.2 + -0.8x2 = 0.0

Add '-231.2' to each side of the equation.
231.2 + -231.2 + -0.8x2 = 0.0 + -231.2

Combine like terms: 231.2 + -231.2 = 0.0
0.0 + -0.8x2 = 0.0 + -231.2
-0.8x2 = 0.0 + -231.2

Combine like terms: 0.0 + -231.2 = -231.2
-0.8x2 = -231.2

Divide each side by '-0.8'.
x2 = 289

Simplifying
x2 = 289

Take the square root of each side:
x = {-17, 17}