Maths problem, thankd?
回答 (2)
2019-08-21 10:19 pm
✔ 最佳答案
From △BAE : ∵AB=AE, ∴△BAE is an isos.△ => base∠s equal
Let the base∠ be θ
2θ+112° = 180°
∴θ= 34°
So, ∠DCF=∠ABE =θ=34° (corr.∠s equal)
Let AB=DA= 1 unit
Let DF = x,
Then FA= 1-x
From △DCF : tan∠DCF = x/1
∴ x = tan 34°
From △ABF, tan∠ABF = (1-x)/1 = 1-tan 34°
∴∠ABF = 18° Ans. (B)
2019-08-21 9:08 pm
The Answer is
D. 26
D. 26
收錄日期: 2021-04-18 18:24:01
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