Copy of Optimization - Art Gallery

A visualization of a classic optimization problem: Where is the best spot to stand to view a painting? A painting in an art gallery has height 3 m and is hung so that its lower edge is about 1 m above the eye of an observer. How far from the wall should the observer stand to get the best view? (i.e. the observer wants to maximize the angel θ subtended at the eye by the painting.)