## Alley Ladders

#### Problem

Two ladders are placed on opposite diagonals in an alley such that one ladder reaches `a` units up one wall, the other ladder reaches `b` units up the opposite wall and they intersect `h` units above the ground.

Prove the following result.

1 a | + | 1 b | = | 1 h |

Problem ID: 127 (Oct 2003) Difficulty: 3 Star