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 ...

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 ...

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 ...

Exactly how many triangles can you count in this fun triangle puzzle?

Click to see a step-by-step guide. STEP 1: Use the ruler to draw a diagonal line from the bottom right corner of the paper to the top left corner. Mark the 90° right angles in the bottom left and top ...

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