Everyone learns the number one rule about triangles in high school: the angles of a triangle add up to 180 degrees. But did you know that sometimes they don't? Triangles are much more interesting than ...

to build on students' knowledge of triangle and develop students' reasoning with properties of different classes of triangles to develop students' language related to different triangles to engage ...

Big Idea – We can describe, measure, and compare spatial relationships. to build on students' knowledge of triangle and develop students' reasoning with properties of different classes of triangles to ...

With all due respect to Pythagoras, newly uncovered evidence suggests that his famous theorem, used to calculate the lengths of each side of a right triangle, might be 1,000 years older than him. That ...