Question 31666
log[b]6x+4(log[b]x-log[b]y) 
= log[b]6x + 4log[b]x - 4log[b]y
= log[b]6x + log[b]x^4 - log[b]y^4
= log[b](6x*x^4/y^4)
= log[b](6x^5/y^4)

The correct option for the answer is A.  When you send "Thank You" message, would you please indicate the grade level that covers such type of logarithmic problems?  Thanks