The team scores points for each touchdown.
Step 1:
Phrase: The team scores points for each touchdown.
Variable: Let represents the number of touchdown.
Expressions: .
Therefore, the algebraic expression is .
Step 2:
Make a table for team scores.
Number of touch downs Input 
Rule

Number of points Output 
Step 3:
Find the domain and range.
Domain: Set of all  coordinates is .
Range: Set of all  coordinates is .
Number of touch downs Input 
Rule

Number of points Output 
The domain is and the range is .
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