Explain how you can use integers chips to determine the sum of 4 + (-8)

You can use chips to determine the sum by subtracting them.

For example, the - 8 would represent 8 chips with a negative sign on the and the 4 would have 4 chips with a postive sign on them. Then you take away or cancel out each number leaving you with 4 negative chips.

I don't know how to use integer chips for the problem - 9 - (-4)