When adding with negatives:
Two negatives make for MORE negative. An example is (-4) + (-3) = -7.
Adding a negative and a positive. There will be cancelling and you keep the sign of the larger absolute value. Example: (-9) + 5 = -4.
When subtracting with negatives:
Keep, change, change. An example is (-8) - (-2) becoming -8 + 2.
When multiplying or dividing with negatives: two negatives will make a positive result and one negative will make a negative result. Examples: 14 / (-2) = -7 and (-5)(-6) = 30.