#### Answer

There are many systems of equations that have this solution set.

#### Work Step by Step

In order to find to sets of linear equations that have $(5,7)$ as their solution set, find two equations that are distinct yet individually have $(5,7)$ as their solution set. Some equations that this is true for are:
$ x + y = 12 $
$ 7x - 5y = 0$
$ 7x + 8y = 91$
$ 2x - y = 3$
In order to find a system of equations with $(5,7)$ as its solution, pick any two equations, and call them a system of equations.