Constraint (mathematics)

Constraints are like a math problem. They tell us what we can use, and what we cannot use, to figure out a solution. It's like a list of rules that you have to follow while solving the problem. For example, it might tell you which numbers you can use, which operations you can use, and even what the solution has to look like. Like a math problem, the only way to figure out the solution is by following the rules that the constraints force us to follow.