Answer:
oh sorry i dont know that im grade six sorry
Answer:
![\left[\begin{array}{ccc}9\\10\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D9%5C%5C10%5C%5C%5Cend%7Barray%7D%5Cright%5D)
Step-by-step explanation:
Evaluate 3a by multiplying each element by 3
3a = 3 ![\left[\begin{array}{ccc}2\\4\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D2%5C%5C4%5C%5C%5Cend%7Barray%7D%5Cright%5D)
= ![\left[\begin{array}{ccc}3(2)\\3(4)\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D3%282%29%5C%5C3%284%29%5C%5C%5Cend%7Barray%7D%5Cright%5D)
= ![\left[\begin{array}{ccc}6\\12&\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D6%5C%5C12%26%5C%5C%5Cend%7Barray%7D%5Cright%5D)
, then
3a + b
= ![\left[\begin{array}{ccc}6\\12\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D6%5C%5C12%5C%5C%5Cend%7Barray%7D%5Cright%5D)
+ ![\left[\begin{array}{ccc}3\\-2\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D3%5C%5C-2%5C%5C%5Cend%7Barray%7D%5Cright%5D)
← sum corresponding elements
= ![\left[\begin{array}{ccc}6+3\\12-2\\\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D6%2B3%5C%5C12-2%5C%5C%5Cend%7Barray%7D%5Cright%5D)
=
You just have to divide all of it and then round it to the nearest tenths if u need too .
Answer:
0.08*x + 0.09*(9000-x) = 750 dollars
0.08x + 810 - 0.09x = 750
-0.01x = 750 - 810 = -60 ====> x = %28-60%29%2F%28-0.01%29 = 6000.
Answer. $6000 was invested at 8%. The rest 9000-6000 = 3000 dollars were invested at 9%.
Check. 0.08*6000 + 0.09*3000 = 480 + 270 = 750 dollars. ! Correct !
have a great day
hope this help
