Working with a set amount of fencing

You have several rolls of fencing and you need to create a rectangular area for your herd of cattle. How can you best make use of the fencing In this case, the better or best use is when you can create the largest possible area. 

Part IV Taking the Shape of Geometric Word Problems 

Sixty feet of fencing creates several areas. 

The areas of the figures created by the same 60 feet of fencing are 200 square units, 125 square units, 29 square units, and 225 square units. The way a certain amount of fencing is used makes a huge difference in the area. 

The Problem You have 680 feet of fencing and want to create a rectangular pasture whose length is 10 feet more than twice its width. What dimensions do you make your pasture  

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