The total perimeter of the pentagon is 19.4cm. One side is 4.6cm, and then the other 4 sides are all equal to each other.
The first thing to do is to take away 4.6 from 19.4 which gets you 14.8cm. You then need to divide 14.8 by 4 to get 3.7.
3.7cm is equal to H.
