The perimeter of a shape is the sum of its side lengths.
The expression for the amount left is 180 - 4x
The length of the fencing is given as:
[tex]\mathbf{Length = 4x}[/tex]
The available length is:
[tex]\mathbf{Available = 180}[/tex]
So, the length of fencing left is the difference between the available length and the length of fencing used.
So, we have:
[tex]\mathbf{Amount\ Left = 180 - 4x}[/tex]
Hence, the expression for the amount left is 180 - 4x
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