Answer:
The valley of ashes between West Egg and New York City consists of a long stretch of desolate land created by the dumping of industrial ashes. It represents the moral and social decay that results from the uninhibited pursuit of wealth, as the rich indulge themselves with regard for nothing but their own pleasure. The valley of ashes also symbolizes the plight of the poor, like George Wilson, who live among the dirty ashes and lose their vitality as a result.
As per convention:
- the angle at A is named A, the angle at B is named B, and the angle at C is named C
- the side of leght a is the side opposed to A, the side of length b is opposed to B, and the side of length c is opposed to C.
Now just state the law of cosines:
c^2 = a^2 + b^2 - 2ab cos(C)
Also, a^2 = c^2 + b^2 - 2bc cos (A)
And, b^2 = a^2 + c^2 - 2ac cos (B)