To find the lengths of the enlarged triangle, we would find the scale factor from the given length
22.5/5 = 4.5
So to find the other sides you would multiply 3 and 6 by 4.5
3 * 4.5 = 13.5
6 * 4.5 = 27
So all 3 lengths of the triangle are 22.5, 13.5, and 27
To find the perimeter you add all
22.5 + 13.5 + 27 = 63
Your answer is 63