Question

What kind of matrix is A? A = \begin{pmatrix} 1 & 2 & 3 \\ 0 & 5 & 7 \\ 0 & 0 & 9 \end{pmatrix}
​⎝
​⎛
​​
​1
​0
​0
​​
​2
​5
​0
​​
​3
​7
​9
​​
​⎠
​⎞
​​

Answer 1

Answer:

Please gove me a point