Perform the indicated operations. 3) $3(4 x+2 y)(4 x-6 y)$

Step 1 ：This is a multiplication of two binomials. To solve this, we can use the distributive property (also known as the FOIL method in this case) to multiply each term in the first binomial with each term in the second binomial. The FOIL method stands for First, Outer, Inner, and Last, which is the order in which we multiply the terms. After that, we multiply the result by 3.

Step 2 ：Perform the operation: \((4x - 6y)(12x + 6y)\)

Step 3 ：Simplify the expression to get: \(12*(2x - 3y)*(2x + y)\)

Step 4 ：\(\boxed{12*(2x - 3y)*(2x + y)}\) is the final answer.