Answer
$25ft$
Work Step by Step
Step 1. Set up a general equation for the parabola: let the vertex of the satellite dish be at the origin and its focus on the $+y$-axis, the general equation can be written as $x^2=4py$, with a focus at $(0,p)$
Step 2. Identify the given conditions: the coordinates of the edge of the rim is given as $(10, 1)$ as shown in the figure of the Exercise.
Step 3. Plug the coordinates in the general equation: $10^2=4p\times1$ and we get $p=25ft$
Step 4. Conclusion: the question asks the location of the focal point and the answer is $25ft$ from the vertex.
