Answer:

Step-by-step explanation:
Use the Pythagorean Theorem:
![\displaystyle a^2 + b^2 = c^2 \\ \\ 9,7^2 + b^2 = 13,3^2; \sqrt{82,8} = \sqrt{b^2} \\ \\ \frac{3\sqrt{230}}{5}\:[or\:9,0994505329...] = b](https://tex.z-dn.net/?f=%5Cdisplaystyle%20a%5E2%20%2B%20b%5E2%20%3D%20c%5E2%20%5C%5C%20%5C%5C%209%2C7%5E2%20%2B%20b%5E2%20%3D%2013%2C3%5E2%3B%20%5Csqrt%7B82%2C8%7D%20%3D%20%5Csqrt%7Bb%5E2%7D%20%5C%5C%20%5C%5C%20%5Cfrac%7B3%5Csqrt%7B230%7D%7D%7B5%7D%5C%3A%5Bor%5C%3A9%2C0994505329...%5D%20%3D%20b)
So, you have this:

I am joyous to assist you at any time.
Answer:
C. True; by the Invertible Matrix Theorem if the equation Ax=0 has only the trivial solution, then the matrix is invertible. Thus, A must also be row equivalent to the n x n identity matrix.
Step-by-step explanation:
The Invertible matrix Theorem is a Theorem which gives a list of equivalent conditions for an n X n matrix to have an inverse. For the sake of this question, we would look at only the conditions needed to answer the question.
- There is an n×n matrix C such that CA=
. - There is an n×n matrix D such that AD=
. - The equation Ax=0 has only the trivial solution x=0.
- A is row-equivalent to the n×n identity matrix
. - For each column vector b in
, the equation Ax=b has a unique solution. - The columns of A span
.
Therefore the statement:
If there is an n X n matrix D such that AD=I, then there is also an n X n matrix C such that CA = I is true by the conditions for invertibility of matrix:
- The equation Ax=0 has only the trivial solution x=0.
- A is row-equivalent to the n×n identity matrix
.
The correct option is C.
Step-by-step explanation:
Sorry I don't know the answeer
Answer:
x=-14
Step-by-step explanation:
If x= x+9=-5 then you do the subtract 9 from both sides to get x = -14