Answer: 244 feet
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Explanation:
Imagine reflecting everything so that location A is above location B. Effectively all you're doing is erasing the negative signs.
That would place A at 290 feet and B would be at 46 feet. The difference in elevation is 290-46 = 244 feet
Instead of reflecting, you can turn the page upside down and just ignore the negative signs, and then subtract like normal.
This trick only works if both elevations A and B are below sea level.
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Or you could subtract like so:
|A-B| = |-290-(-46)| = |-290+46| = |-244| = 244
The absolute value is used to ensure the result is not negative. A negative difference makes no sense. In this case, "difference" and "distance" mean the same thing more or less.
