What is it i’m really really really confused about it lol

it would be D

So, when they say quantities that combine to make 0, that means you have to lose, and then gain the same amount back.

If you look at all the other choices, they either keep on gaining or they don't gain the same amount they lost

Think about it as breaking even.  You aren't actually gaining anything if you are gaining back the exact same amount you lost.

option (b) is correct

step-by-step explanation:

to find the solution of this system, we need to convert it into reduced row-echelon form. we have,

after applying row operations r2 -> r2/2 and r3 -> r3/3, we get,

333.74 ! should be your answer for this question