A farmer wants to fence 60,000 m^2 of land in a rectangular plot along a straight highway. The fence along the highway costs $10 per meter, while the fence for the other three sides cost $5 per meter. How much of each type of fence will have to be bought in order to keep expenses to a minimum? what is the minimum expenses?

Question

tkhunny · Answer

#1 thing to do - Name Stuff!

H = Length of fence parallel to the Highway
L = Length of fence perpendicular to the Highway.

We're almost done.

anonymous · Answer

got it

tkhunny · Answer

You're not going to share?

anonymous · Answer

share what? I only labeled the sides

anonymous · Answer

would the next thing be 60,000=HL

anonymous · Answer

or 3L*H

tkhunny · Answer

I see.  Well, I was hoping you would take it from there.  I thought "got it" meant you had a final result.

Now, let's spill what we know about rectangles, in terms of H and L

Area H * L
Perimeter 2*H + 2*L
However, we're missing a highway side, so only H + 2*L for the total length of fencing.

Where does that leave us?

anonymous · Answer

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