-x - x - 3x - 4x
Let's start from left to right. First do -x - x, which is -2x.
-2x - 3x - 4x
Now do -2x - 3x, which is -5x.
-5x - 4x = -9x
-9x is your answer.
Answer:
2,300
Explanation:
This is given as:

Therefore, there are 2,300 ways that 3 persons can be selected from 25 people
Answer:
8k
Step-by-step explanation:
1. Simplify: -k + 8k
2. -k + 8k = 7k
Answer:
If z<7, then z-7 is negative, and |z-7| is positive. So, with the understanding that z-7 is positive, the first part of this expression becomes:
7-z for z<7
Similarly: if z<7, then z-9 is negative and |z-9| is positive. Thus, -|z-9| is equivalent to (9-z).
|z−7|−|z−9|, if z<7 becomes (7-z) - (9-z) for z<7. Simplifying this, we get:
7 - z - 9 + z = -2