Question

задача 1
(угол) ABC=72 (градусов)
DBC - ABD=26
DBC = ?
ABD = ?

задача 2
MNP=140
MNK : KNP= 2:5
MNK= ?
KNP = ?

Answer 1

1)∠DBC+∠ABD=72°
∠DBC-∠ABD=26°
2DBC=72+26=98   
∠DBC=98/2=49   
∠ABD=72-49=23°

2)∠MNК+∠KNP=140
∠MNК=140-∠KNP
∠MNK:∠KNP= 2/5=0,4
∠MNK=0,4∠KNP
0,4∠KNP=140-∠KNP
0,4∠KNP+∠KNP=140
1,4∠KNP=140
∠KNP=140/1.4=100°
∠MNК=140-100=40°