This sounds like a right triangle and solvable by Pythagorean methods.

c^2 = a^2 + b^2

you are looking for c ( the hypotenuse ), so...

c = sqrt(a^2 + b^2)

c = sqrt(13 m^2 + 9 m^2)

c = sqrt(250)

c = 15.8 meters

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This sounds like a right triangle and solvable by Pythagorean methods.

c^2 = a^2 + b^2

you are looking for c ( the hypotenuse ), so...

c = sqrt(a^2 + b^2)

c = sqrt(13 m^2 + 9 m^2)

c = sqrt(250)

c = 15.8 meters

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Sounds like a major surgeical procedure would entail

You can't.  That's all I have to say.  You can't lose that much in a month's time.