Factor completely. \[ 3 y^{2}+33 y+72 \]

Step 1 ：The given expression is a quadratic equation in the form of ax^2 + bx + c. To factorize it completely, we need to find two numbers such that their sum is equal to the coefficient of y (which is 33 in this case) and their product is equal to the constant term (which is 72 in this case).

Step 2 ：Let's denote y as y. The expression is \(3y^{2} + 33y + 72\).

Step 3 ：We can factorize the expression as \(3*(y + 3)*(y + 8)\).

Step 4 ：Final Answer: The completely factored form of the given expression is \(\boxed{3(y + 3)(y + 8)}\).