Linear depreciation is represented by the equation

.
Therefore, 7 years.
The solution to the system is (-2,-8)
Assume w is the width. the length is 3*2w
To fence the whole outside of farm, he needs:
2(w+6w)=14w meters
Also he needs one width and one length for the enclosed pens. Therefore, the total amount of fencing he would need:
14w+w+6w=21w meters
Answer:
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