The slope of the line is 1. the equation would be y=x-3
The equation of a circle:

where
(h, k) - the coordinates of a center
r - the radius
We have:


<em>Greetings from Brasil...</em>
We know that:
48 = 8 · 6
and 8 - 2 = 6, so
48 = 8 · 6 = 8 · (8 - 2)
then
X · (X - 2) = 48
X · (X - 2) = 8 · 6
<h3>X · (X - 2) = 8 · (8 - 2)</h3>
We can conclude that
<h3>X = 8</h3>