Ответ:

Пошаговое объяснение:

938

ABD = DBC + 20

ABC = 90

ABC = ABD + DBC

ABC = DBC + (DBC+20)

90 = 2DBC+20

2DBC = 90 - 20

2DBC = 70

DBC = 35

ABD = DBC + 20 = 35 + 20 = 55.

939

MOK = MN - KON

MOK = 180 - 120

MOK = 60

MOK = KOL = 60

LON = MN - MOK - KOL = 180 - 60 - 60 = 60

940

1) 2880 : 36 = 80 га

2) S1 = S2 +4

S = S1 + S2

S = (S2+4) + S2

80 = 2*S2 + 4

2*S2 = 80-4

2*S2 = 76

S2 = 38

S1 = S2 +4 = 38 +4 = 42