Simplifying the Expression 12x - 3y + 5x + 7y

To simplify the given expression, combine like terms by adding or subtracting the coefficients of the same variables. In this case:

12x + 5x = 17x -3y + 7y = 4y

Therefore, the simplified expression is:

17x + 4y

Remember to keep the sign in front of each term as it was in the original expression. This helps in accurately representing the operation performed on the terms.