Angles in triangles All triangles have internal angles that add up to 180°, no matter the type of triangle.

Learn how to make half-square triangles, and assemble three rows of a six row sampler quilt. Designs include - Opposing Arrows, Teetering Triangles, and Twirling Triangles.

Learn how to make half-square triangles, and assemble three rows of a six row sampler quilt. Designs include - Opposing Arrows, Teetering Triangles, and Twirling Triangles.

A square has four right angles (90°). Each diagonal splits a corner into two angles of 45°. Note also that the diagonals cut each other in half at right angles. A rectangle has four right angles ...

A sweltering and oppressive heat wave is moving across the U.S. this week, with the Triangle in the thick of the temperature turn-up.