![\left[\begin{array}{cc|c}-1&-1&-12\\-3&2&32\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7Cc%7D-1%26-1%26-12%5C%5C-3%262%2632%5Cend%7Barray%7D%5Cright%5D)
Multiply through row 1 by -1:
![\left[\begin{array}{cc|c}1&1&12\\-3&2&32\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7Cc%7D1%261%2612%5C%5C-3%262%2632%5Cend%7Barray%7D%5Cright%5D)
Add 3(row 1) to row 3:
![\left[\begin{array}{cc|c}1&1&12\\0&5&68\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7Cc%7D1%261%2612%5C%5C0%265%2668%5Cend%7Barray%7D%5Cright%5D)
Multiply through row 2 by 1/5:
![\left[\begin{array}{cc|c}1&1&12\\0&1&\frac{68}5\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7Cc%7D1%261%2612%5C%5C0%261%26%5Cfrac%7B68%7D5%5Cend%7Barray%7D%5Cright%5D)
Add -1(row 2) to row 1:
![\left[\begin{array}{cc|c}1&0&-\frac85\\&&\\0&1&\frac{68}5\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bcc%7Cc%7D1%260%26-%5Cfrac85%5C%5C%26%26%5C%5C0%261%26%5Cfrac%7B68%7D5%5Cend%7Barray%7D%5Cright%5D)
42% of what is 63
0.42x = 63
x = 63/0.42
x = 150
There are 150 dancers in the school
Answer:
-40m = 59.2
Step-by-step explanation:
simplify
Answer:
C
Expand the bracets then simplfy and then factorise