Answer: 15.5
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Work Shown:
c^2 = a^2 + b^2 - 2*a*b*cos(C)
c^2 = 15^2 + 20^2 - 2*15*20*cos(50)
c^2 = 225 + 400 - 600*cos(50)
c^2 = 225 + 400 - 600*0.642787609686539
c^2 = 225 + 400 - 385.672565811924
c^2 = 239.327434188076
c = sqrt(239.327434188076)
c = 15.470211187572
c = 15.5
