The 2 triangle in the figure above share...

The 2 triangle in the figure above share a common side. What is `cos(x+y)`
`("Note : "cos (x+y)=cos xcosy-sinxsiny" for all x and y.")`

A

`(4)/(5)`

B

`(3+4sqrt(24))/(5)`

C

`(4sqrt(24)-3)/(25)`

D

`(3-4sqrt(24))/(25)`

Verified by Experts

The correct Answer is:

D

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