Algebra: Chapter 2, Lesson 8, page 93.
Inverse of a Sum and Simplifying
The inverse of a SUM Property: For any rational numbers, `−(a+b)=−a+(−b)`. The additive inverse of a sum is the sum of the additive inverses.
In other words, if you have a `−` in front of a paranthesis, then just change the sign of EVERYTHING inside.
For example: `−(2a−7b−6)` becomes the opposite of each term, `−2a+7b+6`.
Another example: `3y-2-(2y-4)=3y-2-2y+4`. Combining like terms, we see the answer `=2y-4`