Answer:
1/3
Step-by-step explanation:
To find the scale factor write a ratio from the side length of the small triangle to a corresponding side length of the large triangle.
C'B' has the distance 3 units and CB has the distance 9 units.
The ratio then is 3/9 = 1/3. So the scale factor is 1/3 because it is shrinking the larger triangle to the smaller as shown by the ' marks on the letters.
