There's a roughly linear relationship between the length of someone's femur (the long leg-bone in your thigh) and their expected height, as expressed in the graph below. What is the meaning of the yy-value when x, equals, 55x=55?

I'm sorry, but without the graph you mentioned, I cannot provide the meaning of the y-value when x equals 55. Please provide the graph or any other relevant information, so I can assist you further.