Answer:
(a) SW/VW
Step-by-step explanation:
In similar triangles ΔTUS and ΔVWS, corresponding angles are congruent. That means angle W will have the same measure and trig function values that angle U has.
The mnemonic SOH CAH TOA reminds you that the cosine ratio in this right triangle is ...
Cos = Adjacent/Hypotenuse
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In ΔVWS, the side adjacent to angle W is side SW. The hypotenuse of the triangle is side VW. Then the cosine of interest is ...
cos(U) = cos(W) = SW/VW