What is the solution to the equation 13.7y = 6.2y + 30?

Y = 4

13.7 - 6.2y = 30

7.5 = 30

y = 30

     7.5

y = 4

you didn't post any answer choices, so its not 100% clear what your teacher is looking for

however, log(15/7) is equivalent to log(15) - log(7)

i'm using the rule log(x/y) = log(x) - log(y)