What is the length of ? Round to the nearest tenth.
9.7 m
10.4 m
37.3 m
38.6 m

Using basic trigonometry we can write an equation in COS.
Taking 75° as the angle, its adjacent side is given and we need to find hypotenuse (x). Hence, we use cosine.
We know [tex]cos x=\frac{adjacent}{hypotenuse}[/tex], so we can write,
[tex]cos 75 = \frac{10}{x} \\x=\frac{10}{cos 75} \\x=\frac{10}{0.2588} \\x=38.64[/tex]
The length of x, rounded to one decimal place, is 38.6 meters. Fourth choice is correct.
ANSWER: 38.6 m