What is the approximate value of k?

Hello from MrBillDoesMath!

5.06

Discussion:

Angle J = 180 - (120 + 40) = 180 - 160 = 20 degrees,

From the law of sines

sin(120)/k = sin(20)/2  =>

sin(120) =  k *  (  sin(20)/2) )                (multiply both sides by "k")

k = sin(120)/  (   sin(20)/2)                    (divide both sides by sin(20)/2)

k =  (0.866) /  ( 0.171) =  5.06

Regards,  

MrB

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