To solve this equation, we need to first distribute the numbers on the left side of the equation:

3x(x+2) - 5(x-2) = 3(x^2 - 4)

Expanding the left side:

3x^2 + 6x - 5x + 10 = 3x^2 - 12

Combining like terms:

3x^2 + x + 10 = 3x^2 - 12

Subtracting 3x^2 from both sides to get the variable terms on one side:

x + 10 = -12

Subtracting 10 from both sides:

x = -22

Therefore, the solution to the equation is x = -22.