Answer with Step-by-step explanation:
We are given that
A and B are matrix.
A.We know that for two square matrix A and B
Then, 
Therefore, it is true.
B. det A is the product of diagonal entries in A.
It is not true for all matrix.It is true for upper triangular matrix.
Hence, it is false.
C.

When is a factor of the characteristics polynomial of A then -5 is an eigenvalue of A not 5.
Hence, it is false.
D.An elementary row operation on A does not change the determinant.
It is true because when an elementary operation applied then the value of matrix A does not change.
1/3 of an hour is 20 minutes. If show 10 laps in 5 minutes, just divide 20 by 5, which gives you 4, then multiply 4 times 10. She can swim 40 laps in 1/3 of an hour. Hope that helps. Mark Brainliest if it does. Thank you!
we know that
If a ordered pair (x,y) is a solution of the equation, then the ordered pair must satisfy the equation
we have the equation

Let's verify all the cases to determine the solution to the problem.
<u>case A)</u> point 
Substitute the values of x and y in the equation



-------> is true
therefore
The point
is a solution of the equation
<u>case B)</u> point 
Substitute the values of x and y in the equation



-------> is true
therefore
The point
is a solution of the equation
<u>case C)</u> point 
Substitute the values of x and y in the equation



-------> is not true
therefore
The point
is not a solution of the equation
<u>case D)</u> point 
Substitute the values of x and y in the equation



-------> is not true
therefore
The point
is not a solution of the equation
therefore
<u>the answer is </u>

