(3x+2)(3x-2)=77

Solution for (3x+2)(3x-2)=77 equation:

Simplifying
(3x + 2)(3x + -2) = 77

Reorder the terms:
(2 + 3x)(3x + -2) = 77

Reorder the terms:
(2 + 3x)(-2 + 3x) = 77

Multiply (2 + 3x) * (-2 + 3x)
(2(-2 + 3x) + 3x * (-2 + 3x)) = 77
((-2 * 2 + 3x * 2) + 3x * (-2 + 3x)) = 77
((-4 + 6x) + 3x * (-2 + 3x)) = 77
(-4 + 6x + (-2 * 3x + 3x * 3x)) = 77
(-4 + 6x + (-6x + 9x2)) = 77

Combine like terms: 6x + -6x = 0
(-4 + 0 + 9x2) = 77
(-4 + 9x2) = 77

Solving
-4 + 9x2 = 77

Solving for variable 'x'.

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

Add '4' to each side of the equation.
-4 + 4 + 9x2 = 77 + 4

Combine like terms: -4 + 4 = 0
0 + 9x2 = 77 + 4
9x2 = 77 + 4

Combine like terms: 77 + 4 = 81
9x2 = 81

Divide each side by '9'.
x2 = 9

Simplifying
x2 = 9

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