# Drawing quadrilateral with known edges

Hi guys, could you help me to draw a small quadrilateral with known edges?
So, for example, I have a quadrilateral with edges sequentially 200, 300, 250, and 220, and I need to build it in Rhino…

At least one diagonal line is required to get a quadrilateral from four edges.

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Super. Thank you for the idea.

For just 4 edges the circle intersection method is probably easiest.
For more complex systems you could also use constraints in the Rhino 8 WIP.
A quadrilateral with defined edge lengths still has one degree of freedom - it is a 4 bar linkage.

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how did you get the diagonal?

You can pick a length arbitrarily (within a range) for the diagonal.

yes, but to get to the lenght of the diagonal i would have to make quite some geometric construction which looks from my side like that, but i am just messing around and scratching my head… not sure if thats valid since i am still in the process and seems maybe unnecessary complicated.

You start by drawing the diagonal.
Then put 2 circles at each end point (with radii equal to the length of the 2 connected edges).
Then draw the quad by making lines from the ends to the circle intersections.