The pole is 12 foot long.
The wire from the top to the ground, 6feet from the pole, forms a right angle triangle.
By Pythagoras' Theorem:
x² = 12² + 6²
x² = 144 + 36
x² = 180 Take the square root of both sides.
x = √180 Use a calculator
x ≈ 13.42 feet.
Length of wire ≈ 13.42 feet.