Answer: 72.54
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Step-by-step explanation:
We set up a cosine ratio, since we want to connect the adjacent and hypotenuse. Then we'll use the inverse cosine, which is also known as arccosine, to isolate the angle value.
This is what your steps could look like:
cos(angle) = adjacent/hypotenuse
cos(L) = LM/LN
cos(L) = 18/60
cos(L) = 0.3
L = arccos(0.3)
L = 72.542396876278 which is approximate
L = 72.54 degrees approximately
Make sure your calculator is in degree mode.