With geometry , i set up the equation like 5x+9=3x+11 and got 1 but that's not the right answer

So, you put the values on the other sides of the vertical angles, so you get a set of interior angles (can't remeber word at the moment)
Make the angles equal to 180.
So equation looks like 3x+11+5x+9=180.
Now combine like terms, get 8x+20=180.
Subtract 20 from both sides and get 8x=160.
Divde both sides by 8 and get your answer of x= 20
Hope this helps

Letter a i would say

The answer would be (c)