# Practical Math - Hanging a 48" high mirror at the proper height

How high must a 48-inch high mirror be hung if one who is six feet tall needs to see his entire image from approximately 6 feet away from the mirror?

-
I think this should be moved to physics.stackexchange.com because it involves the physics of mirror images. –  000 Dec 7 '12 at 11:25
@Limitless: I think in mathematics we can get away with assuming that the angle of incidence equals the angle of reflection, without worrying particularly about the physical reasons why it is so. –  Henning Makholm Dec 7 '12 at 12:02
@HenningMakholm My physics knowledge is not that great, and I did not want to make assumptions. That is why I was concerned; I was erring on the side of caution. –  000 Dec 7 '12 at 12:07
@Limitless: not migrating is erring on the side of caution :-) –  robjohn Dec 7 '12 at 12:16
@robjohn Thanks for clarifying! :-) –  000 Dec 7 '12 at 12:17

So, $2$ feet is the required height