120=0.5c^2

Solution for 120=0.5c^2 equation:

Simplifying
120 = 0.5c2

Solving
120 = 0.5c2

Solving for variable 'c'.

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

Add '-0.5c2' to each side of the equation.
120 + -0.5c2 = 0.5c2 + -0.5c2

Combine like terms: 0.5c2 + -0.5c2 = 0.0
120 + -0.5c2 = 0.0

Add '-120' to each side of the equation.
120 + -120 + -0.5c2 = 0.0 + -120

Combine like terms: 120 + -120 = 0
0 + -0.5c2 = 0.0 + -120
-0.5c2 = 0.0 + -120

Combine like terms: 0.0 + -120 = -120
-0.5c2 = -120

Divide each side by '-0.5'.
c2 = 240

Simplifying
c2 = 240

Take the square root of each side:
c = {-15.491933385, 15.491933385}