The triangles here are each obtained by applying rigid motions to Triangle 1.
21 congruent triangle. 3 rows of 7 triangles, labeled one through 15. Odd numbered triangles point upwards, even numbered triangles point downwards. Top row has labels 9 through 15, middle row has labels 5 through 11, bottom row has labels 1 through 7.
Which triangles are translations of Triangle 1? Explain how you know.
Which triangles are not translations of Triangle 1? Explain how you know.
Angle is congruent to angle . Name another pair of congruent angles. Explain how you know.
Horizontal line segment m passes through points D and E. Horizontal line segment l passes through points A and C. Diagonal line A B passes through point D. Diagonal line B C passes through point E.