Common difference (d) = - 14-(-17)
d = -14+17
d = 3...
Tn = -17+(n-1)3
Tn = - 17+3(n-1)
Option a is correct.....
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)
Answer:
8
Step-by-step explanation:
There are 4 possible ways he could have written it: chalk, pen, pencil, and marker.
There are 2 ways he wrote it: French and English
4*2=8
He wrote his name in 8 different ways.
The answer is 12+3r because 4 times 3=12 then the 3r which you cannot add because they are no others variables that are r
Third, the graph decreases from left to right because if you plug it into a graphing calculator - you can see that the line is a straight line, and does not decrease or increase whatsoever