If A and B are equal:
Matrix A must be a diagonal matrix: FALSE.
We only know that A and B are equal, so they can both be non-diagonal matrices. Here's a counterexample:
![A=B=\left[\begin{array}{cc}1&2\\4&5\\7&8\end{array}\right]](https://tex.z-dn.net/?f=A%3DB%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7D1%262%5C%5C4%265%5C%5C7%268%5Cend%7Barray%7D%5Cright%5D)
Both matrices must be square: FALSE.
We only know that A and B are equal, so they can both be non-square matrices. The previous counterexample still works
Both matrices must be the same size: TRUE
If A and B are equal, they are literally the same matrix. So, in particular, they also share the size.
For any value of i, j; aij = bij: TRUE
Assuming that there was a small typo in the question, this is also true: two matrices are equal if the correspondent entries are the same.
A
- Harvard university professor
Answer: The correct option is
(E) 80,000.
Step-by-step explanation: Given that after adding 4,000 gallons of water to a large tank that was already filled to 
of its capacity, the tank was then at 
of its capacity.
We are to find the number of gallons of water that the tank hold when filled to capacity.
Let the tank can hold x gallons of water when filled to capacity.
Then, according to the given information, we have
Thus, the required capacity of the tank is 80,000 gallons of water.
Option (E) is CORRECT.
Answer: Yes. The cookies are $ .75 each. The total cost is proportional to the number of cookies purchased.
T = $.75 × c
Step-by-step explanation:
We begin with 1,000 fish in a lake.
Each year the population declines to 15%
Then they put back 500 fish in the lake.
The equation: (1000 * .85) +500
