Answer:
P = 60
Step-by-step explanation:
First, to find the scale factor, or how much bigger the other shape is, you can do so by comparing the two triangles' longest sides.
25 5
---- = ----
15 3
So the larger triangle is 5/3 times bigger.
This means that all of its other sides with also be 5/3 times bigger.
So:
9 (5/3) = 45/3 = 15
12 (5/3) = 60/3 = 20
25 + 15 + 20 = 60
So the perimeter is 60.
You could have also found the perimeter of the smaller triangle, 9 + 12 + 15 = 36, then multiplied it by the scale factor, which would be:
36 (5/3) = 180/3 = 60
You would get the same thing.
