The formula n(n+1)/2
1 answer:
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<h2>Explanation:</h2><h2 />
Hello! Remember you have to write complete questions in order to get good and exact answers. Here I'll help you assuming some things. First of all, for a two dimensional shape, the perimeter is defined as the distance around it. Suppose we have a rectangle whose dimensions are:
So in this context:
Correct option is D. 10x - 20