Answer
$\text{ approximately } 24 \text{ } ft$
Work Step by Step
Let $x$ be the height from the ground where the wire will be attached. Using $a^2+b^2=c^2$ or the Pythagorean Theorem, the conditions of the problem translate to
\begin{array}{l}\require{cancel}
15^2+x^2=(30-2)^2
.\end{array}
Using the properties of equality, the equation above is equivalent to
\begin{array}{l}\require{cancel}
x^2=(30-2)^2-15^2
\\
x^2=28^2-15^2
\\
x^2=784-225
\\
x^2=559
.\end{array}
Taking the square root of both sides, the equation above is equivalent to
\begin{array}{l}\require{cancel}
x=\sqrt{559}
\\
x\approx24
.\end{array}
Hence, the height from the ground where the wire will be attached, $x,$ is $
\text{ approximately } 24 \text{ } ft
.$
