Please do not spam the same question, I have already answered it.
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:
E. 2 1/2
E. 8.5 cm
C. 6 cm
Step-by-step explanation:
4............................
Scale factor = AE/AC = (4+6)/4 = 10/4 = 2.5
<u>Correct option is</u> E. 2 1/2
5............................
DE = ?
- DE = √AD² - AE² = √15² - 10² = √125 = 5√3 ≈ 8.66
- <em>For measure of AD see next question (6)</em>
<u>Close option is</u> E. 8.5 cm
6............................
AB = ?
- AD/AB = 2.5 <em>the scale factor as per question 4</em>
- (AB + 9)/AB = 2.5
- 2.5*AB = AB + 9
- 1.5*AB = 9
- AB = 9/1.5
- AB = 6 cm
<u>Correct option</u> C. 6 cm