19.15=0.864x*x

Solution for 19.15=0.864x*x equation:

Simplifying
19.15 = 0.864x * x

Multiply x * x
19.15 = 0.864x2

Solving
19.15 = 0.864x2

Solving for variable 'x'.

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

Add '-0.864x2' to each side of the equation.
19.15 + -0.864x2 = 0.864x2 + -0.864x2

Combine like terms: 0.864x2 + -0.864x2 = 0.000
19.15 + -0.864x2 = 0.000

Add '-19.15' to each side of the equation.
19.15 + -19.15 + -0.864x2 = 0.000 + -19.15

Combine like terms: 19.15 + -19.15 = 0.00
0.00 + -0.864x2 = 0.000 + -19.15
-0.864x2 = 0.000 + -19.15

Combine like terms: 0.000 + -19.15 = -19.15
-0.864x2 = -19.15

Divide each side by '-0.864'.
x2 = 22.16435185

Simplifying
x2 = 22.16435185

Take the square root of each side:
x = {-4.707903127, 4.707903127}