Respuesta :

Answer:21y^4= B*7y^3

B=(21y^4)/(7y^3)

B=3y

i think this is correct

Answer and Step-by-step explanation:

The guy above me is correct. I input it and got it right. Somehow I can't just seem to comment on their answer... Well, I am just answering this for points and to help future people who might look for the answer. Here, I have a screenshot of it from Khan Academy...

Hope this helps and thank won't hurt! :)

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