How long must a wire be to reach from the top of a 13 meter telephone pole to a point on the ground 9 meters from the foot of the pole?

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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