KA)BAD = BHD BA = BH B) KẺ BM EK BM = AE = AB = BH BMK = BHK...
Bài3:
Ka)BAD = BHD BA = BH
b) Kẻ BM EK BM = AE = AB = BH
BMK = BHK góc B3
= góc B
4
HMà, góc B
1
= góc B
2
AECgóc B
1
+ góc B
2
+ góc B
3
+ góc B
4
= 90
0
D góc DBK = góc B2
+ góc B
3
= 45
0