∫ED again //OP? ∴∠PHD=75

And ∵OP ∠ xoy ∴∠ Poe = 45? ∴∠ BCO = 60 (the sum of the three internal angles of a triangle is 180).

∫ AC bisection ∠ BCE ∠ BCO = 60.

∴∠BCA =( 180-60)∴2 = 60∴∠PAC = 60+( 180-75)= 165(。

2,? ∵∠D=75？ ∴∠BDF= 180 -75 = 105

∫∠BCA = 60 (with proof on it)? ∴∠BCA =∞∠DCF = 60° (equal to the vertex angle)? ∴∠f= 180-60- 105 = 15？

I don't know what is the relationship between ∠F and ∠BCO. ...

3 Prove ① ∵∠ D = ∠ BDE = 75? GD split ∠BDE? ∴∠BDG=∠GDE=37.5

∠∠BCO =∠BCA =∠ Ace = 60? ∴∠ACD= 180 -∠BCA= 120？ ∴∠ cmd =180-∠ ACD-∠ ADB = 22.5 ∴∠ GMA = ∠ cmd = 22.5 (equal to the vertex angle)? ∫∠PAC = 165 (the answer to the first question)? ∴∠gam= 180-∠PAC = 180- 165 = 15？ ∴∠GMA≠∠GAM

Prove that ②∫GD divides equally ∠ BDE ∠ D = ∠ BDE = 75? ∴∠ OGD =∠ BDE ∠ 2 = 752 = 37.5 (two straight lines are parallel and the internal dislocation angles are equal) and ∠ BCO =∠ DCE = 60 (the opposite vertex angles are equal) ∴∴ (2 ∠.