9514 1404 393
Answer:
21.4
Step-by-step explanation:
For this problem, you only need to know that the hypotenuse (x) is the longest side of the triangle. The only answer choice longer than 20 is ...
x = 21.4
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If you want to actually go through the numbers, you know that ...
Cos = Adjacent/Hypotenuse
cos(21°) = 20/x
x = 20/cos(21°)
x ≈ 21.4
