Final answer:
To simplify the expression (7x+12)-(4x+9), distribute the negative sign and then combine like terms to get the simplified expression 3x + 3.
Step-by-step explanation:
To simplify the expression (7x+12)-(4x+9), we can start by distributing the negative sign in front of the second parentheses. This gives us 7x + 12 - 4x - 9. Using these values, you can substitute them into the formula and calculate the future amount in your account. Next, we can combine like terms by combining the x terms and the constant terms separately. So, 7x - 4x simplifies to 3x, and 12 - 9 simplifies to 3.
Therefore, the simplified expression is 3x + 3.