# Definition: 4.2: Rectilinear Figure Circumscribed about Another Rectilinear Figure

And, similarly, a (rectilinear) figure is said to be circumscribed about a(nother rectilinear) figure when the respective sides of the circumscribed (figure) touch the respective angles of the (figure) about which it is circumscribed.

### Modern Formulation

A rectilinear figure $$A$$ is said to be circumscribed about another rectilinear figure $$B$$, if and only if all the sides of $$A$$ pass through the vertices of $$B$$. In this case, $$B$$ is inscribed in $$A$$.

### Example

The $$4$$-sided figure $$A B C D$$ is circumscribed about the $$4$$-sided figure $$E F G H$$, and the $$4$$-sided figure $$E F G H$$ is inscribed about the $$4$$-sided figure $$A B C D$$, :

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### References

#### Bibliography

1. Byrne, O.: "The First Six Books of the Elements of Euclid, in Which Coloured Diagrams and Symbols are used Instead of Letters", London William Pickering, 1847