Hello from MrBillDoesMath!
Answer:
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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