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### Functions that Describe Situations

After seeing a pattern, do you ever wonder what the rule is behind the pattern? It is the function rule. A * FUNCTION RULE* is a rule that assigns every input to an output which follows one rule, like a formula.

The notation used for representing a function is .

If a question states that creating a membership plan requires a one time transaction of $10 and a montly payment of 5$, the easy way to solve these type of questions is to create a function rule to represent the question.

Payment = (10$) + = 10$ + 5*x*

With this funtion, we are able to easily solve the questions as long as we have this simple funtion rule.

For some practice problems and examples, you can visit this page here.