Answer: I believe the answer is triangles b and e
Explanation:
Translations preserve side length and the do not rotate they only move right and left and/or up and down. Therefor f is out because the sides get larger and a is out because it would be a reflection of the xaxis and d is out because it would a reflection over the yaxis. C and g are both rotations. This is why only B and E are translations of triangle y.
I hope this helps and makes sense! Let me know!