Answer:
D. ![\left[\begin{array}{ccc}-12&-4\\9&3\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D-12%26-4%5C%5C9%263%5Cend%7Barray%7D%5Cright%5D)
Step-by-step explanation:
In order for a matrix to be singular, the determinant has to be zero.
Answer:
82 websites per year.
Step-by-step explanation:
take the difference in the number of websites from both years, divide it by the year difference (9) to find how many per year were created
If you add the two equations together,
Ex:
-3x-4y=2
+ 3x+4y=-3
————————
0=-1
So there is no solution