∫BD divided equally ∠ABC FG⊥BC
∴∠BFG=90 -? ∠ABC=67.5
∠∠ABC = 45∠ACB = 65
∴∠BAC=70
∫∠BFH is the outer corner of △ABF.
∴∠BFH=? ∠ABC+? ∠BAC=57.5
∴∠hfg=∠bfg-∠bfh=67.5-57.5 = 10
(2)
According to the idea in (1)
∠BFG=90 -? ∠ABC
∠BFH=? ∠ABC+? ∠BAC
=? ∠ABC+? ( 180 -∠ABC-∠ACB)
=90 -? ∠ACB
∴∠HFG=∠BFG-∠BFH
=? (∠ACB-∠ABC)
(3)BFH =∠CFG
Reason:
∫∠BFH is the outer corner of △ABF.
∴∠BFH=? (∠ABC+∠BAC)
In the right triangle FGC,
∠CFG=90 -? ∠ACB
=90 -? ( 180 -∠ABC-∠BAC)
=? (∠ABC+∠BAC)
Therefore, ∠BFH=∠CFG.
The method may not be the simplest, and the answer is for reference only.
It's done.