Answer:
Using the AA similarity postulate, you can determine that these triangles are similar.
Explanation:
All three triangles are right triangles, so they all have 90° angles.
Angle B is present in the large and small triangle. Therefore, you know those 2 triangles are similar. You can also prove that angles A and C are the same.
A and B are complementary angles in the large triangle and the same with B and C in the small one. Since B ≅ B by Reflexive Property, A and C must have the same angle measurement since they are complements of the same angle.