SOLUTION: Find BC using sine and cosine laws. Diagram is here: https://imgur.com/a/QfMV35Y

Algebra ->  Trigonometry-basics -> SOLUTION: Find BC using sine and cosine laws. Diagram is here: https://imgur.com/a/QfMV35Y      Log On


   

Question 1147674: Find BC using sine and cosine laws.
Diagram is here: https://imgur.com/a/QfMV35Y
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
angle BAD = 180 -90 -8 = 82 degrees
:
10/sin(8) = BD/sin(82)
:
BD = 10 * sin(82)/sin(8) = 71.15
:
angle CDE = 180 -85 -90 = 5 degrees
:
angle CDA = 90 + 5 = 95 degrees
:
angle DAC = 180 -95 -11 = 74 degrees
:
10/sin(11) = CD/sin(74)
:
CD = 10 * sin(74)/sin(11) = 50.38
:
BC^2 = (71.15)^2 +(50.38)^2 -2 *(71.15) *(50.38) *cos(85)
:
BC^2 = 6975.64
:
BC = 83.52
: