### Short Version

- Arrange the puzzle pieces to form a convex shape without overlapping.
- Drag pieces around the grid; use the buttons below to rotate and flip them.
- Each convex shape you find will be captured in the “trophy boxes” to the right.
- Find as many different shapes as you can!

### What is a convex shape? What shapes are accepted?

Imagine a rubber band closing around the shape. The shape is convex if the band snaps tight against every edge. If the band leaves any gaps, then the shape is *not* convex.

Convex
Band Snaps Tight
Not Convex
Band Leaves Gaps

The three colorful examples at the top of the page are *not* convex. The four below *are* convex, although they use pieces from a different puzzle.

Read more about convex polygons at at Mathworld or at Math Open Reference

### More Details and Fine Print

- Pieces always snap to the grid, with their vertices at grid points.
- Rotations are only in 60° increments, so some orientations of the pieces are not possible.
- You can use the r, d, and f keys to rotate and flip, if you have a keyboard.
- I know of twelve different convex shapes. Maybe you'll find a thirteenth?
- You can also just play with the pieces and build shapes however you like.

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