Answer: Choice A) 44
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Work Shown:
cos(angle) = adjacent/hypotenuse
cos(X) = 13/18
X = arccos(13/18)
X = 43.7617 approximately
X = 44
Side note: The arccosine function is the same as inverse cosine as notated by [tex]\cos^{-1}[/tex]. Make sure your calculator is in degree mode.