Two angles are congruent if they have the same measure. You already know that when two lines intersect the vertical angles formed are congruent. You have also seen that if ∠A and ∠B are each complementary to ∠C, then ∠A ~= ∠B. There are other angle relationships to explore. When you expose these angle relationships, you will establish their truth using a formal proof.
任天堂Switch的电源和音量键的更换
