Answer:
We can not solve for a unique cost for each soldier.
Explanation:
Let x be the daily cost for legionaries and y be the daily cost for archers.
Upon using our given information we will get a system of linear equations as:


Now we will solve for x from our 2nd equation,

Now we will substitute this value in our 1st equation.

We can see that -3y cancels out with 3y and 9 is not equal to 10. So this is an unsolvable system. Therefore, we can not find a unique cost for each soldier.