Question

Where to put the black point to show all the angles that are congruent to angle A

Answer 1

Explanation:

as I see it, A is the full 180° angle.

and so, there are 3 more 180° angles:

below A in the other side of the blue line the whole 180° arc.

above and below the blue line at the intersection point with the second, parallel red line (again, the whole 180° arcs).

Answer 2

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