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已知,∠ABD:∠CBD = 1: 1 ,∠ABE:∠CBE = 2:5 ,可得:
∠ABD/∠ABC = ∠ABD/(∠ABD+∠CBD) = 1/(1+1) = 1/2 ,即有:∠ABD = (1/2)∠ABC ;
∠ABE/∠ABC = ∠ABE/(∠ABE+∠CBE) = 2/(2+5) = 2/7 ,即有:∠ABE = (2/7)∠ABC ;
因为,∠DBE = ∠ABD-∠ABE = (1/2-2/7)∠ABC = (3/14)∠ABC ,
所以,∠ABC = (14/3)∠DBE = 126° 。 赞同0| 评论
∠ABD/∠ABC = ∠ABD/(∠ABD+∠CBD) = 1/(1+1) = 1/2 ,即有:∠ABD = (1/2)∠ABC ;
∠ABE/∠ABC = ∠ABE/(∠ABE+∠CBE) = 2/(2+5) = 2/7 ,即有:∠ABE = (2/7)∠ABC ;
因为,∠DBE = ∠ABD-∠ABE = (1/2-2/7)∠ABC = (3/14)∠ABC ,
所以,∠ABC = (14/3)∠DBE = 126° 。 赞同0| 评论
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已知,∠ABD:∠CBD = 1: 1 ,∠ABE:∠CBE = 2:5 ,可得:
∠ABD/∠ABC = ∠ABD/(∠ABD+∠CBD) = 1/(1+1) = 1/2 ,即有:∠ABD = (1/2)∠ABC ;
∠ABE/∠ABC = ∠ABE/(∠ABE+∠CBE) = 2/(2+5) = 2/7 ,即有:∠ABE = (2/7)∠ABC ;
因为,∠DBE = ∠ABD-∠ABE = (1/2-2/7)∠ABC = (3/14)∠ABC ,
所以,∠ABC = (14/3)∠DBE = 126° 。
∠ABD/∠ABC = ∠ABD/(∠ABD+∠CBD) = 1/(1+1) = 1/2 ,即有:∠ABD = (1/2)∠ABC ;
∠ABE/∠ABC = ∠ABE/(∠ABE+∠CBE) = 2/(2+5) = 2/7 ,即有:∠ABE = (2/7)∠ABC ;
因为,∠DBE = ∠ABD-∠ABE = (1/2-2/7)∠ABC = (3/14)∠ABC ,
所以,∠ABC = (14/3)∠DBE = 126° 。
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已知,∠ABD:∠CBD = 1: 1 ,∠ABE:∠CBE = 2:5 ,可得:
∠ABD/∠ABC = ∠ABD/(∠ABD+∠CBD) = 1/(1+1) = 1/2 ,即有:∠ABD = (1/2)∠ABC ;
∠ABE/∠ABC = ∠ABE/(∠ABE+∠CBE) = 2/(2+5) = 2/7 ,即有:∠ABE = (2/7)∠ABC ;
因为,∠DBE = ∠ABD-∠ABE = (1/2-2/7)∠ABC = (3/14)∠ABC ,
所以,∠ABC = (14/3)∠DBE = 126° 。
∠ABD/∠ABC = ∠ABD/(∠ABD+∠CBD) = 1/(1+1) = 1/2 ,即有:∠ABD = (1/2)∠ABC ;
∠ABE/∠ABC = ∠ABE/(∠ABE+∠CBE) = 2/(2+5) = 2/7 ,即有:∠ABE = (2/7)∠ABC ;
因为,∠DBE = ∠ABD-∠ABE = (1/2-2/7)∠ABC = (3/14)∠ABC ,
所以,∠ABC = (14/3)∠DBE = 126° 。
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已知,∠ABD:∠CBD = 1: 1 ,∠ABE:∠CBE = 2:5 ,可得:
∠ABD/∠ABC = ∠ABD/(∠ABD+∠CBD) = 1/(1+1) = 1/2 ,即有:∠ABD = (1/2)∠ABC ;
∠ABE/∠ABC = ∠ABE/(∠ABE+∠CBE) = 2/(2+5) = 2/7 ,即有:∠ABE = (2/7)∠ABC ;
因为,∠DBE = ∠ABD-∠ABE = (1/2-2/7)∠ABC = (3/14)∠ABC ,
所以,∠ABC = (14/3)∠DBE = 126° 。
∠ABD/∠ABC = ∠ABD/(∠ABD+∠CBD) = 1/(1+1) = 1/2 ,即有:∠ABD = (1/2)∠ABC ;
∠ABE/∠ABC = ∠ABE/(∠ABE+∠CBE) = 2/(2+5) = 2/7 ,即有:∠ABE = (2/7)∠ABC ;
因为,∠DBE = ∠ABD-∠ABE = (1/2-2/7)∠ABC = (3/14)∠ABC ,
所以,∠ABC = (14/3)∠DBE = 126° 。
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