Answer:
6 kg pecans,
2 kg cashews.
Explanation:
Let x be the weight of cashews and y be the weight of pecans in kg.
We have been given that the owner of a shop wants to mix cashews and pecans to make 8 kg of mixed nuts. We can represent this information in an equation as:

We are also told that the mixed nuts worth $7.25 per kg, so the price of 8 kg of mixed nuts will be
.
Since the price of cashews is $8.00 per kg and the price of pecans is $7.00 per kg, so we can represent this information in an equation as:
Now we will use substitution method to solve system of equations.
From equation (1) we will get,

Substituting this value in equation (2) we will get,






Therefore, the owner should take 6 kg of pecans.
Upon substituting
in equation (1) we will get,



Therefore, the owner should take 2 kg of cashews.