As shown in the figure, it is known that in △ ABC, D is a point on the edge of BC, ∠ 1 = ∠ B, ∠ 2 = ∠ C, ∠ BAC = 78 ° to find the degree of ∠ DAC
∫∠ BAC + ∠ B + ∠ C = 180 °, ∫ B + ∠ C = 180 ° - 78 ° = 102 °, ∫ 2 = ∠ B + ∠ 1, and ∠ 1 = ∠ B, ∫ C = ∠ 2, ∫ C = 2 ∠ 1, ∫ 1 + 2 ∠ 1 = 102 °, ∫ 1 = 34 °, ∫ DAC = ∠ BAC - ∠ 1 = 78 ° - 34 ° = 44 °
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