The new length side of the perimeter, we'll call p. The original length, we'll call o. P's equation looks like this:

Since 5 is the length of one side, subtract 2 from 5 to get 3. The equation looks like this:

or simply
Answer:
we know that q=-18
So if we see the fraction below it says q/3
We know that q is -18
Therefore, you substitute it in for q and you get
-18/3 which equals -6
4/5 is the the fraction of a pound is eighty pence