Distance of point A is f/2
Ref image .1
Let A′ is the image of A from mirror, for this image
1/v + 1/(-f/2) = 1/(-f)
1/v = 2/f - 1/f = 1/f
v = f
Ref image .2
Image of line AB should be perpendicular to the principle axis
image of F will form at infinity, therefore correct image diagram is
Ref image.3
f/(f-u) = h2/h1
h2 = -f(f-x)/(-f+x)
h2 = f.