Question

I need help on number 12

Answer 1

Angle ACD and angle CAD are angles that add to 90 degrees (60+30 = 90) and they are non-adjacent. They do not share a common vertex. So this is why the two angles fit the description for number 12.

In contrast, two adjacent complementary angles are angle FDG and angle GDE. They add to 90 degrees and share the common vertex point D. They also share a common segment DG.