Answer: cos(B) = 9 / 41
Reasoning:
1) Remember the definition of the ratio cosine:
For a right triangle, cos(x) = adjacent-leg / hypotenuse.
2) The figure shows that for the angle B, the adjacent leg is 27 and the hypotenuse is 123.
3) So, use the formula to find cos(B):
cos(B) = 27/123.
4) Simplify the fraction: 27 / 123 = 9 / 41.
Answer: 9 / 41