Answer:
B
Explanation:
We are given the equation:

And that:

And we want to find the value of y / x.
To start, subtract x from both sides in the first equation:

Divide both sides by x:

Simplify:

Next, in the second equation, divide everything by two:

Substitute:

Simplify:

From the modified second equation, we can multipy both sides by 1/3:

Substitute:

Subtract:

Therefore, our answer is B.