The graph represents function 1 and the equation represents function 2: how much more is the rate of change of function 2 than the rate of change of function 1?

Problem number 26 of the rhind papyrus says: find a quantity such that when it is added to of itself the result is a 15. the modern day equation that models this problem is x + x = 15. what is the solution to the equation? x = 10 x = 12 x = 15 x = 30