Find the standard form for the equation of a circle x h2 y
Find the standard form for the equation of a circle (x - h)^2 + (y - k)^2 = r^2 with a diameter that has endpoints (-9, -10) and (3, -10). h = k = r =
Solution
1) end points ( -9 , -10) and ( 3, -10)
Centre h = ( -9 +3)/2 = -3
k = ( -10 -10)/2 = -10
(h, k) = ( -3, -10)
diameter = distance between the two endpoints = sqrt(( 3- -9)^2 + (-10 +10)^2 )) = 12
radius , r, = 12/2 = 6
2) Centre ( 6, 5)
So, A = 6 ; B = 5
Circle is tangent to the y axis , so, radius = x coordinate of circle = 6
C = 6
