(3+9i)(3-9i)=

Solution for (3+9i)(3-9i)= equation:

Simplifying
(3 + 9i)(3 + -9i) = 0

Multiply (3 + 9i) * (3 + -9i)
(3(3 + -9i) + 9i * (3 + -9i)) = 0
((3 * 3 + -9i * 3) + 9i * (3 + -9i)) = 0
((9 + -27i) + 9i * (3 + -9i)) = 0
(9 + -27i + (3 * 9i + -9i * 9i)) = 0
(9 + -27i + (27i + -81i2)) = 0

Combine like terms: -27i + 27i = 0
(9 + 0 + -81i2) = 0
(9 + -81i2) = 0

Solving
9 + -81i2 = 0

Solving for variable 'i'.

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

Add '-9' to each side of the equation.
9 + -9 + -81i2 = 0 + -9

Combine like terms: 9 + -9 = 0
0 + -81i2 = 0 + -9
-81i2 = 0 + -9

Combine like terms: 0 + -9 = -9
-81i2 = -9

Divide each side by '-81'.
i2 = 0.1111111111

Simplifying
i2 = 0.1111111111

Take the square root of each side:
i = {-0.333333333, 0.333333333}