18ab-(-11c-12bc)

To simplify the expression \(18ab - (-11c - 12bc)\), you need to distribute the negative sign across the terms inside the parentheses.

Here are the steps:

1. Distribute the negative sign: \[ 18ab - (-11c - 12bc) = 18ab + 11c + 12bc \]

So, the simplified expression is: \[ 18ab + 11c + 12bc \]