Step-by-step explanation:

Answer:
x=[15:-5:-25]'
Step-by-step explanation:
In order to create a vector you need to use this command:
x = [j:i:k]'
This creates a regularly-spaced vector x using i as the increment between elements. j is the initial value and k is the final value. Besides you need to add the character ' at the end in order to convert the arrow vector in a column vector
Answer:
The value of x in terms of b is: 
The value of x when b is 3 is: x = -1
Step-by-step explanation:
We are given the function: 
First we need to find
The value of x in terms of b
We need to find value of x

Multiply -2 with terms inside the bracket

Subtract 10 from both sides

Divide both sides by -2b

So, The value of x in terms of b is: 
The value of x when b is 3
We have the equation for the value of x in terms of b:

Put b = 3

So, The value of x when b is 3 is: x = -1