As shown in the figure, it is known that ∠ B = ∠ C. If ad ‖ BC, does ad divide ∠ EAC equally? Please give reasons

Ad bisecting ∠ EAC for the following reasons: ∵ ad ‖ BC, (known) ∵ B = ∠ ead, (two parallel lines, equal angles) ∵ C = ∠ DAC, (two parallel lines, equal angles) ∵ B = ∠ C, (known) ∵ ead = ∠ DAC. (equivalent substitution) ∵ ad bisecting ∠ EAC. (definition of angle bisecting line)

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15. As shown in the figure, BD bisects ∠ ABC, be bisects ∠ ABC into two parts of 2:5, ∠ DBE = 27 ° and calculates the degree of ∠ ABC
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