As shown in the figure:
The two cables and the ground like as an equilateral triangle
The length of each side = 14 m
The pole is perpendicular to the ground
So, there are two right angle triangle
From the left side triangle:
hypotenuse = 14 m
And the length from the cable to the pole = 14/2 = 7 m
Let the height of the pole = h
Using Pythagorean theorem:
[tex]\begin{gathered} 14^2=7^2+h^2 \\ h^2=14^2-7^2=196-49 \\ h^2=147 \\ h=\sqrt[]{147}=\sqrt[]{3\cdot49}=7\sqrt[]{3} \end{gathered}[/tex]
So, the height of the pole = 7√3 meters.