Respuesta :

Answer:

D. 3

Step-by-step explanation:

If the prisms are said to the similar, that means that the ratio/relation between their corresponding sides have to equal, so

[tex]\frac{x}{1} = \frac{9}{3} = \frac{30}{10}[/tex]

We can easily use the part x/1 = 9/3 to make a cross-multiplication that would give us:

x = (1 * 9) / 3 = 9/3 = 3

So, the green prism is a dilated version of the blue one by a dilation/scale factor of 3.