Physics 102 help.....................

Question

A man standing 1.52 m in front of shaving mirror produces an inverted image 18.0 cm in front of it. How close to the mirror should he stand if he wants to form an upright image of his chin that is twice the actual size of his chin?

is the answer 8 cm or 20 cm please explain

Answer 1

u=1.52m(dist from object)

v=18cm=0.18m(dist from image)or v=?(not sure)

Magnification=?

Height of O=x

Height of I=2x

M=v/f-1  2x/x=v/I don't know why I can't finish it?