Triangles in Ten Shapes Puzzle

Directions: Each shape below has 1-10 triangles in it. Find the number of triangles in each shape.

triangle puzzle image

 

bar image

Hint: There are shapes that have 1 triangle, 2 triangles, 3 triangles, 4 triangles, and so on up to 10 triangles.

Dr. Robert Sweetland's notes
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