mark must leave it for 5.5 months or 5 and half moths to gain 5600 in interest .
<u>Step-by-step explanation:</u>
Here we have , mark invests 8000 in an account that pays 12% interest and 2000 in one that pays 8%. if he leaves the money in the accounts for the same length of time, We need to find how long must he leave it to gain 5600 in interest . Let's find out:
Let mark invests 8000 in an account that pays 12% interest and 2000 in one that pays 8% for time x months , So total interest gain is 5600 i.e.
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Therefore , mark must leave it for 5.5 months or 5 and half moths to gain 5600 in interest .
Answer:
its Pp or it could also be nonexistent
Basically
just put the coeficinets of each variable in the apropriate row
example
ax+by=c and
dx+ey=f
would go in like this
![\left[\begin{array}{ccc}a&b&|c\\d&e&|f\end{array}\right]](https://tex.z-dn.net/?f=%20%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7Da%26b%26%7Cc%5C%5Cd%26e%26%7Cf%5Cend%7Barray%7D%5Cright%5D%20)
so
3x+1=1 and
0x-1y=5
![\left[\begin{array}{ccc}3&1&|1\\0&-1&|5\end{array}\right]](https://tex.z-dn.net/?f=%20%20%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D3%261%26%7C1%5C%5C0%26-1%26%7C5%5Cend%7Barray%7D%5Cright%5D%20)
D is answer