Answer:
![A)\ \ \ \ \left[\begin{array}{ccc}8&-5\\-3&2\\\end{array}\right]](https://tex.z-dn.net/?f=A%29%5C%20%5C%20%5C%20%5C%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D8%26-5%5C%5C-3%262%5C%5C%5Cend%7Barray%7D%5Cright%5D)
Step-by-step explanation:
Given the matrix: ![\left[\begin{array}{ccc}2&5\\3&8\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D2%265%5C%5C3%268%5C%5C%5Cend%7Barray%7D%5Cright%5D)
, it's inverse is calculated using the formula:
![\left[\begin{array}{ccc}a&b\\c&d\\\end{array}\right]^{-1}=\frac{1}{det\left[\begin{array}{ccc}a&b\\c&d\\\end{array}\right] }\left[\begin{array}{ccc}d&-b\\-c&a\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Da%26b%5C%5Cc%26d%5C%5C%5Cend%7Barray%7D%5Cright%5D%5E%7B-1%7D%3D%5Cfrac%7B1%7D%7Bdet%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Da%26b%5C%5Cc%26d%5C%5C%5Cend%7Barray%7D%5Cright%5D%20%7D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Dd%26-b%5C%5C-c%26a%5C%5C%5Cend%7Barray%7D%5Cright%5D)
#Therefore, we calculate as;
![\frac{1}{det\left[\begin{array}{ccc}2&5\\3&8\\\end{array}\right] }\left[\begin{array}{ccc}8&-5\\-3&2\\\end{array}\right] \\\\\\\\\#det\left[\begin{array}{ccc}2&5\\3&8\\\end{array}\right] =1\\\\\\\\=\frac{1}{1}\left[\begin{array}{ccc}8&-5\\-3&2\\\end{array}\right] \\\\\\\\=\left[\begin{array}{ccc}8&-5\\-3&2\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7Bdet%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D2%265%5C%5C3%268%5C%5C%5Cend%7Barray%7D%5Cright%5D%20%7D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D8%26-5%5C%5C-3%262%5C%5C%5Cend%7Barray%7D%5Cright%5D%20%5C%5C%5C%5C%5C%5C%5C%5C%5C%23det%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D2%265%5C%5C3%268%5C%5C%5Cend%7Barray%7D%5Cright%5D%20%3D1%5C%5C%5C%5C%5C%5C%5C%5C%3D%5Cfrac%7B1%7D%7B1%7D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D8%26-5%5C%5C-3%262%5C%5C%5Cend%7Barray%7D%5Cright%5D%20%5C%5C%5C%5C%5C%5C%5C%5C%3D%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D8%26-5%5C%5C-3%262%5C%5C%5Cend%7Barray%7D%5Cright%5D)
Hence, the inverse of the matrix is ![\left[\begin{array}{ccc}8&-5\\-3&2\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D8%26-5%5C%5C-3%262%5C%5C%5Cend%7Barray%7D%5Cright%5D)
Hi there! I can help you.
Rate: To find the rate, let’s divide interest earned by the principal. When you do, you get 0.15. Multiply by 100 to get 15 and divide by 3 to get 5. The simple interest rate is 5%.
New balance: All you have to do is add the principal and he new balance. When you do, you get 517.5. The new balance is $517.50.
