72=i^2(8)

Solution for 72=i^2(8) equation:

Simplifying
72 = i2(8)

Reorder the terms for easier multiplication:
72 = 8i2

Solving
72 = 8i2

Solving for variable 'i'.

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

Add '-8i2' to each side of the equation.
72 + -8i2 = 8i2 + -8i2

Combine like terms: 8i2 + -8i2 = 0
72 + -8i2 = 0

Add '-72' to each side of the equation.
72 + -72 + -8i2 = 0 + -72

Combine like terms: 72 + -72 = 0
0 + -8i2 = 0 + -72
-8i2 = 0 + -72

Combine like terms: 0 + -72 = -72
-8i2 = -72

Divide each side by '-8'.
i2 = 9

Simplifying
i2 = 9

Take the square root of each side:
i = {-3, 3}