Answer:
22.5 cm
Step-by-step explanation:
In the figure attached the graph of the problem can be seen.
Given the triangles are similar then the next proportion must be satisfied:
13.5/9 = 18/12 = x/15 = 1.5
Isolating x, we get:
x/15 = 1.5
x = 1.5*15
x = 22.5 cm
