Question 460891
Given oblique triangle ABC, find the length of c: b = 3 a = 4 angle C = 40° 
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Using Law of Cosines:c^2=a^2+b^2-2*a*b*cos C
c^2=4^2+3^2-2*4*3*cos 40º
c^2=16+9-24 cos 40
c^2=6.61
c=√6.61=2.57