F(2)=4(2)-3=5
f(6)=4(6)-3=21
The equation is -3x/y
Plug in the numbers given for x and y
-3(10)/-3.5
-30/-3.5
divide and that's your answer
Answer: 
We have something in the form log(x/y) where x = q^2*sqrt(m) and y = n^3. The log is base 2.
===========================================================
Explanation:
It seems strange how the first two logs you wrote are base 2, but the third one is not. I'll assume that you meant to say it's also base 2. Because base 2 is fundamental to computing, logs of this nature are often referred to as binary logarithms.
I'm going to use these three log rules, which apply to any base.
- log(A) + log(B) = log(A*B)
- log(A) - log(B) = log(A/B)
- B*log(A) = log(A^B)
From there, we can then say the following:

Answer:
x=7
Step-by-step explanation:
expand 4(x+5): 4x+20
2x+34=4x+20
subtract 34 from both sides
2x+34-34=4x+20-34
2x=4x-14
subtract 4x from both sides
2x-4x=4x-14-4x
-2x=-14
divide both sides by -2
-2x/-2=-14/-2
x=7