∠ABC and ∠CBD are
(A) complementary
(B) supplementary
(C) congruentes
(D) vertical

Answer:
(B) Supplementary.
Step-by-step explanation:
Note that ABD is a straight line, which means that the total angle measurement is 180°. When two angles (∠ABC & ∠DBC respectively) are combined and form a straight line (180°), they are known as supplementary angles.
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