Find cable lengths AB and BC the angle C and the angle at Ba
Find cable lengths AB and BC, the angle C, and the angle at B(angle ABC).
Solution
22\' 7\" = 271 \" ; 26\' 8\" = 320 \"
In triangle ABD, apply sine rule:
65deg50\'= 65.83 deg ;
320/sin65.83 = 271/sinB
sinABD = (sin65.83*271)/320 = 0.772
ABD = 50.59 deg
Angle BDA = 180 - 65.83 -50.59 = 63.58 deg
Again applying sine rule : AB/sin63.58 = 320/sin65.83
AB = 314.11 inch = 26\'2\"
Triangle:BCD
Angle BDC = 180 - 63.58 = 116.42 deg
BD = 320\" ; CD = 342\"
Applying cosine rule : BC^2 = BD^2 + CD^2 -2BD*CDcos116.42
BC^2 = 320^2 + 342^2 -2*342*320cos116.42
BC = 562.80 \" = 46\' 11\"
Applying sine rule : BD/sinC = BC/sinD
sinC = BD*sinD/BC = 320*sin116.42/562.80
C = 30.61 deg
Angle DBC = 180 - 30.61 - 116.42 = 32.97 deg
AngleB = 50.59 +32.97 = 83.56 deg
