Question 1059828
find an equation of the circle whose diameter has endpoints (3, -5)  and  (3, 1). 
<pre>Center of circle: (3, - 2)
{{{(x - h)^2 + (y - k)^2 = r^2}}} ------ Center-radius form of equation of circle
{{{(3 - 3)^2 + (1 - - 2)^2 = r^2}}} -------- Substituting point (3, 1) for (x, y) and center (3, - 2) for (h, k)
{{{9 = r^2}}} ======> r 
Equation of circle: {{{highlight_green((x - 3)^2 + (y + 2)^2 = 9)}}}
Anyone who says otherwise is WRONG!