Answer:
∠6, ∠10
Step-by-step explanation:
Apparently, we are to assume that the avenues are parallel.
The angles that form a linear pair with ∠8 will be supplementary: ∠6 and ∠7. The angles that correspond to those will also be supplementary to angle 8: ∠10 and ∠11.
Among the answer choices ∠3, ∠4, ∠6, ∠10, only ∠6 and ∠10 are equal to 180° -x.
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Additional comment
It appears we are to assume that 1st Ave is parallel to 2nd Ave. If that is the case, then we might also assume that D Street is perpendicular to those avenues. In that case, all of angles 5, 6, 7, 9, 10, 11, 12 are equal to 180° -x, because x and all of those are all 90°.