i believe the last leg will be 5, because it should be a 3,4,5 triangle
you are making it bigger, and so you must multiply 3 to each side (dilate means to become wider)
3 x 3 = 9
4 x 3 = 12
5 x 3 = 15
9, 12, 15 are you triangle side lengths
To find perimeter, add them together
15 + 12 = 27
27 + 9 = 36
Your perimeter is 36
hope this helps
