Answer: Choice B) 12
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Step-by-step explanation:
We will use the law of sines which is
sin(A)/a = sin(B)/b
A and B are the angles, with 'a' and 'b' as the opposite sides (side 'a' is opposite angle A, b is opposite angle B)
In this case, we have A = 4x, a = 35, B = 84, and b = 47, so we can say...
sin(A)/a = sin(B)/b
sin(4x)/35 = sin(84)/47
sin(4x) = 35*sin(84)/47
sin(4x) = 0.7406014 ..... make sure your calc is in degree mode
4x = arcsin(0.7406014)
4x = 47.7826708
x = 47.7826708/4
x = 11.9456677
x = 12 .... rounding to the nearest whole number