The answer would be C)3-x/x(x-1)
So you will need to solve for x and y before evaluating 2x+y....
2x-y=9, y=2x-9 now this will make 4x^2-y^2=171 become:
4x^2-(2x-9)^2=171
4x^2-(4x^2-36x+81)=171
36x-81=171
36x=252
x=7, now we can use 2x-y=9 to solve for y...
2(7)-y=9
14-y=9
-y=-5
y=5
now we know that x=7 and y=5, 2x+y becomes:
2(7)+5
14+5
19
Answer: 15
Step-by-step explanation:
First you had subtract by ten from both sides of equation form.

Then simplify by equation.

Final answer: 
Hope this helps!
And thank you for posting your question at here on brainly, and have a great day.
-Charlie