.5z^2-15=0

Solution for .5z^2-15=0 equation:

Simplifying
0.5z2 + -15 = 0

Reorder the terms:
-15 + 0.5z2 = 0

Solving
-15 + 0.5z2 = 0

Solving for variable 'z'.

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

Add '15' to each side of the equation.
-15 + 15 + 0.5z2 = 0 + 15

Combine like terms: -15 + 15 = 0
0 + 0.5z2 = 0 + 15
0.5z2 = 0 + 15

Combine like terms: 0 + 15 = 15
0.5z2 = 15

Divide each side by '0.5'.
z2 = 30

Simplifying
z2 = 30

Take the square root of each side:
z = {-5.477225575, 5.477225575}