The sum of two numbers is 17 and their difference is 29. write the system of equations and solve using the best method. what are the two numbers?

Let's do this algebraically

x + y = 17      (subtract)
-(x - y = 29)

x + y = 17
-x + y = -29

2y = -12        divide both by 2
y = -6          use this in an original equation

x + y = 17
x - 6 = 17      add 6 to both sides
x = 23

our numbers are 23 and -6

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