What’s the scale factor going from Figure 1 to Figure 2?

Greetings from Brasil...
Just compare the distances AC and A'C'. We can see that AC = 2 and A'C' = 6. We can mount the following expression:
AC · X = A'C'
2 · X = 6
X = 6 ÷ 2
X = 3
Thus, figure 2 is 3x larger than figure 1
scale factor = 3x larger