To find the cofactor of
![A=\left[\begin{array}{ccc}7&5&3\\-7&4&-1\\-8&2&1\end{array}\right]](https://tex.z-dn.net/?f=A%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D7%265%263%5C%5C-7%264%26-1%5C%5C-8%262%261%5Cend%7Barray%7D%5Cright%5D)
We cross out the Row and columns of the respective entries and find the determinant of the remaining 
matrix with the alternating signs.
Therefore in increasing order, we have;
Answer:
A rectangle is defined by its length = L, and its width = W.
So the perimeter of the of the rectangle can be written as:
Perimeter = 2*L + 2*W.
In this case, we want to leave the perimeter fixed, so we have:
24ft = 2*L + 2*W.
Now, we do not have any other restrictions, so to know the different dimensions now we can write this as a function, by isolating one of the variables.
2*L = 24ft - 2*W
L = 12ft - W.
or:
L(W) = 12ft - W.
Such that:
W must be greater than zero (because we can not have negative or zero width).
And W must be smaller than 12ft (because in that case we would have zero or negative length)
Then the possible different dimensions are given by:
L(W) = 12ft - W
0ft < W < 12ft.
Answer:
3x5
Step-by-step explanation:
Simply using the given formula ,
I = P × R × t
I = 100 × 10/100 × 3
I = $30
