I figured out (a) ---- 100 degrees.
What is the answer of (b)?
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Would you answer 1 question on maths?
回答 (2)
2014-07-01 11:47 pm
✔ 最佳答案
∠ BAD = 30° (opposite angles are supplementary)AB . . . 7 . . . . . . . . . . ∠BDA . . . 7
----- = ----, therefore --------- = ----
AD . . . 8 . . . . . . . . . . ∠DBA . . . 8
Since ∠ BAD = 30°, then ∠BDA +∠DBA = 150°
so ∠DBA = (8/15)150° = 80°
You have already found that ∠ABC = 100°,
therefore ∠DBC = 100° - 80° = 20°
2014-07-01 3:00 am
20
收錄日期: 2021-04-16 16:33:08
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