Answer:
System of equations:

Augmented matrix:
![\left[\begin{array}{cccc}1&2&2&6\\2&1&1&6\\1&1&3&6\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D1%262%262%266%5C%5C2%261%261%266%5C%5C1%261%263%266%5Cend%7Barray%7D%5Cright%5D)
Reduced Row Echelon matrix:
![\left[\begin{array}{cccc}1&2&2&6\\0&1&1&2\\0&0&1&1\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D1%262%262%266%5C%5C0%261%261%262%5C%5C0%260%261%261%5Cend%7Barray%7D%5Cright%5D)
Step-by-step explanation:
Convert the system into an augmented matrix:
![\left[\begin{array}{cccc}1&2&2&6\\2&1&1&6\\1&1&3&6\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D1%262%262%266%5C%5C2%261%261%266%5C%5C1%261%263%266%5Cend%7Barray%7D%5Cright%5D)
For notation, R_n is the new nth row and r_n the unchanged one.
1. Operations:

Resulting matrix:
![\left[\begin{array}{cccc}1&2&2&6\\0&-3&-3&-6\\0&-1&1&0\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D1%262%262%266%5C%5C0%26-3%26-3%26-6%5C%5C0%26-1%261%260%5Cend%7Barray%7D%5Cright%5D)
2. Operations:

Resulting matrix:
![\left[\begin{array}{cccc}1&2&2&6\\0&1&1&2\\0&-1&1&0\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D1%262%262%266%5C%5C0%261%261%262%5C%5C0%26-1%261%260%5Cend%7Barray%7D%5Cright%5D)
3. Operations:

Resulting matrix:
![\left[\begin{array}{cccc}1&2&2&6\\0&1&1&2\\0&0&2&2\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D1%262%262%266%5C%5C0%261%261%262%5C%5C0%260%262%262%5Cend%7Barray%7D%5Cright%5D)
4. Operations:

Resulting matrix:
![\left[\begin{array}{cccc}1&2&2&6\\0&1&1&2\\0&0&1&1\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcccc%7D1%262%262%266%5C%5C0%261%261%262%5C%5C0%260%261%261%5Cend%7Barray%7D%5Cright%5D)
Option A
If f(x) =
and g(x) =
then 
<em><u>Solution:</u></em>
Given that f(x) =
and g(x) = 
To find: (f - g)(x)
We know that,
(f – g)(x) = f (x) - g(x)
Let us substitute the given values of f(x) and g(x) in above formula,

For solving the brackets in above expression,
There are two simple rules to remember:
When you multiply a negative number by a positive number then the product is always negative.
When you multiply two negative numbers or two positive numbers then the product is always positive.
So the expression becomes,

Combining the like terms,

Thus option A is correct
Answer:
11= 21
12= -12
13= -72
14= -1
Step-by-step explanation:
The answer 2 your question is 24in