So if ∠X is 70° then ∠Y is most likely going to be 70° as well. So if you take 180° which is a straight line and subtract both of the 70°'s you'd get 40°. This answer seems pretty accurate to me.
Step-by-step explanation:
Hope this helps you out! :)
(If any question s put them below and I'll try my best to answer them)
