The sum of two numbers is 13. Their difference is 3. Write a system of equations to model this situation

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What is the solution to the equation below? 3/x-2+6=square root x-2 +8

20.ju inces. which ordered pair is a viable solution if x represents the number of books he orders and y represents the total weight of the books, in ounces? (-3,-18) (-0.5, -3) (0,0) (0.5, 3)