How to determine if the triangles are similar .

For 1 i would say the fact that all three sides are different makes them the same type of triangle. For 2 i would say the fact that all three sides are different and they are both right triangles. For 3 i would say the fact that they are both the same type of triangle (right triangle) that they are the same For 4 i would say the fact that they are both the same triangle.