How do you find the area when you only know the perimeter?

Answer 1

It depends on the figure you talk about; for example:

• If circle: the Diameter D = perimeter/(Pai)

Then the area = Pai x D2 / 4

• If square: the side length L = perimeter/4

Then the area = L2

• If rectangle: then you should know either the length of one sides of the rectangle or to know the ratio of length to width.
  • If you know either the length L or the width W, then you get unknown L or W from the equation:

Perimeter = 2 x (L+W); then the area = L x W

• If you know the ration x = L/W, then L = yW

perimeter = 2 (L + W) = 2 (yW +W) = 2 W (y +1)

Accordingly, you get W value and you get L value (=yW)

Then the area = L x W

=====================================

Wonderful.

Except that the question clearly stated "you only know the perimeter".

So at every point where you postulate additional information, such as

the category of the shape, or one dimension of the rectangle, you've

clearly gone beyond the situation specified in the question.