# Find area of constructed shape on sketch

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

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