Sorting by Sides: The Octopus Tea Party

It’s the Octopus Tea Party under the sea! Octavia has cut the sandwiches into triangles of every kind, and teacups sit in neat rows on the lace tablecloth.

Remember: Triangles also get names from their sides: equilateral has 3 equal sides, isosceles has 2 equal sides, and scalene has no equal sides. Equal sides go with equal angles: an isosceles triangle has 2 equal angles, and a scalene triangle’s angles are all different. The perimeter is the distance all the way around: add all 3 sides.

Magic trick: Count the matching sides: 3, 2 or none.