what is the answer to 12x squared y cubed /2xy squared +6xy * y squared +6y+9 /3y cubed +9y squared?

You have not written an equation, only an algebraic function, with two variables. You need to add parentheses to clarify the order of operations. There is no "answer". It can only be rewritten in other ways.

To simplify the expression (12x^2y^3/2xy^2 + 6xy) * (y^2 + 6y + 9)/(3y^3 + 9y^2), we can break it down into smaller steps:

Step 1: Simplify the first fraction:
The numerator of the first fraction is 12x^2y^3, and the denominator is 2xy^2. To simplify, we can cancel out common factors. Canceling out y^2 and xy from the numerator and denominator respectively, we get:
(12x^2y^3)/(2xy^2) = (12x^2y^3)/(2xy^2) = (6x)/1

Step 2: Simplify the second fraction:
The second fraction is (y^2 + 6y + 9)/(3y^3 + 9y^2). This expression cannot be further simplified.

Step 3: Combine the simplified fractions:
Now, we have (6x)/1 * (y^2 + 6y + 9)/(3y^3 + 9y^2).

So, the simplified expression is (6x(y^2 + 6y + 9))/(3y^3 + 9y^2).

Note: This is simply a simplification of the given expression. If you were looking to solve an equation or find a specific value for x and y, you would need additional information or context.