The question is an illustration of bearing (i.e. angles) and distance (i.e. lengths)
The distance between both lighthouses is 5783.96 m
I've added an attachment that represents the scenario.
From the attachment, we have:
Convert to degrees
Convert to degrees
So, the measure of angle S is:
---- Sum of angles in a triangle
The required distance is distance AB
This is calculated using the following sine formula:
Where:
So, we have:
Make AB the subject
Hence, the distance between both lighthouses is 5783.96 m
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