2y and __ are the same

Which of the following is a justification used while proving the similarity of triangles lom and mon

In a small section of a stadium there are 40 spectators watching a game between the cook islands and fiji. they all support at least one of the two teams. 25 spectators support the cook islands and 16 of these support both teams. how many support only fiji?

Is ofat (-25, 0), (25, 0) co- (0, -15), (0, 15)?