Answer:
x = 21
Step-by-step explanation:
Answer:
Step-by-step explanation:
The sum of two matrices is the sum of corresponding terms.
![\left[\begin{array}{ccc}3&1&0\\-1&2&4\\9&7&-2\end{array}\right] +\left[\begin{array}{ccc}5&2&4\\1&12&3\\11&3&-2\end{array}\right] =\left[\begin{array}{ccc}8&3&4\\0&14&7\\20&10&-4\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D3%261%260%5C%5C-1%262%264%5C%5C9%267%26-2%5Cend%7Barray%7D%5Cright%5D%20%2B%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D5%262%264%5C%5C1%2612%263%5C%5C11%263%26-2%5Cend%7Barray%7D%5Cright%5D%20%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D8%263%264%5C%5C0%2614%267%5C%5C20%2610%26-4%5Cend%7Barray%7D%5Cright%5D)
The formula
a(n) = 2 - 5(n-1)
is in the form
a(n) = a1 + d(n-1)
where
a1 = first term = 2
d = -5 = common difference
The first term is carried over to the recursive formula. We start with a1 = 2. The next term after that is found by subtracting 5 from the previous term. So
second term = (first term) - 5
third term = (second term) - 5
and so on
The recursive step would be
a(n) = a(n-1)-5
So that's why the answer is choice C