Use either the red and black chip model or the traditional algorithm. What is (-4) + (-9) ?

Either it is - 13 or - 5, but if you add them together, since they are neghatives, they should be - 13, but if they are adding a negative and a positive, you would subtract them. It is (-13) that is your answer. If you add two negative together, it would be a negative. If you add a positive and a negative, like - 5+8, you would have more positives than negative, so forth, your answer would be a positive. But for this one, it is (-13). That is your answer.

So it would be - 4 and if there is a + sign and a - sign then always think that its - because if you multiplied it then negative always rules. So it would really be - 4 - 9 which is - 13