Assume that x, y, and a are positive numbers. Use the properties of logarithms to write the expression log a 9 xy in terms of the logarithms of x and y.

Question

a. 9logbx+9logby
b. 19 l o g b ( x + y )
c. 19 l o g b x + l o g b y
d. logbx+logby
e. 19 l o g b x + 19 l o g b y

Answer 1

Where does the b come from in all your answers?
Where does the 19 come from in all the answers?

I suspect a typo

Answer 2

Since log(xy) = log(x) + log(y)

regardless of the base, and considering the chance of typos, I'd go with (e)