Please answer correctly

5,600 x 10^3 = a) 560 b) 5,000,600 c) 5,600,000 d) 56,000

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

The sum of four times a number and three is two times the number minus twenty nine