Answer: 5.6 cm
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Work Shown:
Apply the cosine ratio to find the adjacent side AB
cos(angle) = adjacent/hypotenuse
cos(B) = AB/BC
cos(62) = AB/12
12*cos(62) = AB
AB = 12*cos(62)
AB = 5.6336587534307
AB = 5.6 cm
Make sure your calculator is in degree mode.