I have an arc of known distance (I don't know what other information is needed for an arc but I can supply it) with two lines of known distance that form a right angle. From this arc I need two things. First I need a function that describes x for any h (where x and h form a right angle). Second I need to draw an arc which for any h has a measure of x + 2/3x. Any suggestions are appreciated.

I have provided an attachment showing the setup I am talking about.