<prompt> Calculate the answer to the following expression: 2x 3y - 3x 3y.  <response>: The answer to the expression 2x 3y - 3x 3y is calculated as follows: 1. Distribute the negative sign on the second term to make it -3x - 3y2. Combine like terms: - 2x and -3x combine to make - x- 3y and -3y combine to make 03. So, the final answer is -x. 