To evaluate this expression, we need to remember that subtracting a negative number is the same as adding a positive number, and that adding a negative number is the same as subtracting a positive number. Using this knowledge, let's begin to simplify the expression below:
-1 - 3 - (-9) + (-5)
Because addition of a negative number is the same as subtraction of a positive number, we can change + (-5) to -5, as shown below:
-1 - 3 - (-9) - 5
Next, because we know that subtracting a negative number is the same as adding a positive number, we can change - (-9) to + 9, as shown below:
-1 - 3 + 9 - 5
Now, we can subtract the first two terms and begin to evaluate our expression:
-4 + 9 - 5
Next, we can add the first two numbers of the expression:
5 - 5
Now, we can subtract our last two numbers, which gives us our answer:
0
Therefore, your answer is 0.
Hope this helps!