(-x-9i)(x-9i)=0

Solution for (-x-9i)(x-9i)=0 equation:

Simplifying
(-1x + -9i)(x + -9i) = 0

Reorder the terms:
(-9i + -1x)(x + -9i) = 0

Reorder the terms:
(-9i + -1x)(-9i + x) = 0

Multiply (-9i + -1x) * (-9i + x)
(-9i * (-9i + x) + -1x * (-9i + x)) = 0
((-9i * -9i + x * -9i) + -1x * (-9i + x)) = 0

Reorder the terms:
((-9ix + 81i2) + -1x * (-9i + x)) = 0
((-9ix + 81i2) + -1x * (-9i + x)) = 0
(-9ix + 81i2 + (-9i * -1x + x * -1x)) = 0
(-9ix + 81i2 + (9ix + -1x2)) = 0

Reorder the terms:
(-9ix + 9ix + 81i2 + -1x2) = 0

Combine like terms: -9ix + 9ix = 0
(0 + 81i2 + -1x2) = 0
(81i2 + -1x2) = 0

Solving
81i2 + -1x2 = 0

Solving for variable 'i'.

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

Add 'x2' to each side of the equation.
81i2 + -1x2 + x2 = 0 + x2

Combine like terms: -1x2 + x2 = 0
81i2 + 0 = 0 + x2
81i2 = 0 + x2
Remove the zero:
81i2 = x2

Divide each side by '81'.
i2 = 0.01234567901x2

Simplifying
i2 = 0.01234567901x2

Take the square root of each side:
i = {-0.111111111x, 0.111111111x}