Find the equation for the circle with a diameter whose endpoints are (3,1) and (2,1)

hello :
an equation of the circle Center at the A(a,b) and ridus : r is :
(x-a)² +(y-b)² = r²
in this exercice : a = (3+2)/2 = 5/2   and  b = (1+1)/2 =1

let : B(3;1)    and ; C (2,1)

r = BC/2

BC =  √(3-2)²+(1-1)² )  =1

r = 1/2

a

step-by-step explanation: