## Algebra 1 Tutorial

#### Intro

Use function notation, evaluate functions for inputs in their domains, and interpret statements that use function notation in terms of a context.

#### Sample Problem

Vincent goes to the gym for 30 minutes everyday. He starts a new exercise routine on a Monday and uses a function to model the amount of calories he has used, f(d), as a function of the number of days, d, he has exercised with the new routine.
Which statement represents a correct interpretation of f(d)?

f(5)=150 means Vincent has exercised for a total of 150 minutes after the fifth day of exercising with his new routine.

f(10)=3,500 means Vincent will use 3,500 calories on day 10 of exercising with his new routine.

f(15)=5,250 means after 15 days of exercising with his new routine, Vincent has used 5,250 calories.

f(30)=10,500 means the number of calories Vincent has used times 30 is equal to 10,500.

#### Solution

To solve this problem students must understand that this represents an input of 15, d, and an output of 5,250, f(d). So after 15 days of exercising with the new routine, Vincent has used 5,250 calories.
The work and steps for this problem may vary.
Step 1: write a function using the information in the word problem.
Step 2: evaluate the function with specific values for the variable by plugging, or substituting, in the value and solving. 