I’m thinking this either can’t be done (yet), can be done with stuff not released, or tough to do. Thought I would ask anyway.
So, a student draws a polygon with rotational symmetry on a sketch. They are asked to find the area of the shape they draw. CL checks the area. Here is the activity I am working on, slide 6-1.11 Polygons • Activity Builder by Desmos
Love that “…” animation while checking work.
We can’t (yet!) pull anything out from a geometry component with CL, but if the student clicks on the interior of the polygon and selects “Label”, we will show them the area.
As a sketch, I’m pretty confident there can’t be a way to calculate area. There wouldn’t be a good way for the computer to distinguish between strokes being used to form the border of the shape, and strokes being used to fill the interior.
With a graph component, you could have them manipulate vertices and then use the shoelace formula (! such a cool formula) to have the graph calculate the area: Graphing Calculator