Respuesta :

B. 5 is the answer
3*3 =9
5*3=15
Since they are similar, 
[tex] \frac{9}{3} = \frac{15}{x} [/tex]
Cross Multiply
[tex]3*15=9x[/tex]
[tex]x= \frac{45}{9} =5 [/tex]
So the answer is B.
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