-8z^2+20+28=0

Solution for -8z^2+20+28=0 equation:

Simplifying
-8z2 + 20 + 28 = 0

Reorder the terms:
20 + 28 + -8z2 = 0

Combine like terms: 20 + 28 = 48
48 + -8z2 = 0

Solving
48 + -8z2 = 0

Solving for variable 'z'.

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

Add '-48' to each side of the equation.
48 + -48 + -8z2 = 0 + -48

Combine like terms: 48 + -48 = 0
0 + -8z2 = 0 + -48
-8z2 = 0 + -48

Combine like terms: 0 + -48 = -48
-8z2 = -48

Divide each side by '-8'.
z2 = 6

Simplifying
z2 = 6

Take the square root of each side:
z = {-2.449489743, 2.449489743}