4 1 ... job. 3 1 Fill in: entertain, on holiday, scores, well- paid, event, throw, checks. Every time - id1729839820220627 от TheFlyHelp 27.06.2022 10:09

Question

Геометрия: 4 1 ... job. 3 1 Fill in: entertain, on holiday, scores, well- paid, event, throw, checks. Every time their team the fans start celebrating. 2 Dana is a doctor. It s a(n) Mascots ... ... sweets to the fans to them. A waterslide tester waterslides all around the world to see if they are safe. 5 Alikhan often goes .. to Turkey. 6 The match between the two basketball teams is the main of the week. 4​

TheFlyHelp · Accepted Answer

АС1/С1В=1/1, ВА1/А1С=3/7, АВ1/В1С=1/3, S A1B1C1=S ABC - S AC1B1 - S C1BA1 - S A1CB1, обе части уравнения делим на S ABC

S A1B1C1 / S ABC = 1 - (S AC1B1/S ABC) - (S C1BA1/ S ABC) - (S A1CB1/S ABC)

S ABC=1/2*AB*AC*sinA, S AB1C1=1/2*AC1*AB1*sinA, AB=AC1+C1B=1+1=2, AC=AB1+B1C=1+3=4, S AB1C1/S ABC=(AC1*AB1)/(AB*AC)=(1*1)/(2*4)=1/8,

S ABC=1/2*AB*BC*sinB, S C1BA1=1/2*C1B*BA1*sinB, BC=BA1+A1C=3+7=10,

S C1BA1/S ABC=(C1B*BA1)/(AB*BC)=(1*3)/(2*10)=3/20,

S ABC=1/2*AC*BC*sinC, S A1CB1=1/2*A1C*B1C*sinC, S A1CB/S ABC=(A1C*B1C) / (AC*BC)=(7*3)/(4*10)=21/40,

S A1B1C1/S ABC=1-1/8-3/20-21/40=8/40=1/5, или S ABC/S A1B1C1=5/1

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