20=60-8x^2

Solution for 20=60-8x^2 equation:

Simplifying
20 = 60 + -8x2

Solving
20 = 60 + -8x2

Solving for variable 'x'.

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

Add '8x2' to each side of the equation.
20 + 8x2 = 60 + -8x2 + 8x2

Combine like terms: -8x2 + 8x2 = 0
20 + 8x2 = 60 + 0
20 + 8x2 = 60

Add '-20' to each side of the equation.
20 + -20 + 8x2 = 60 + -20

Combine like terms: 20 + -20 = 0
0 + 8x2 = 60 + -20
8x2 = 60 + -20

Combine like terms: 60 + -20 = 40
8x2 = 40

Divide each side by '8'.
x2 = 5

Simplifying
x2 = 5

Take the square root of each side:
x = {-2.236067978, 2.236067978}