Writing a Function Rule Chapter 5 Sec. 4   page 254-259

 *What is a function rule?

A Function rule is an equation that describes a function 

 *So how do you write a function rule?

 Formula: f(x)=x+d

    d=difference of x and f(x)               For example:    X    f(x)  

                                                                                  1    7         =x+6

                                                                  2   8       =x+6                                                   

                                                                 3   9        =x+6

                                                               f(x)= x+6

 Real World Problem Solving

For example:

A) The total cost t(c) of c ounces of cinnamon if each ounce costs $.79

t(c)=.79c

 Real World Problem Solving 2

For example:

A) You borrowed money from your mom to buy a vacuum for $52. You charge $5 each room.

Write a rule to describe your profit as a function of the # of rooms vacuumed.

p=5x-52

B) How much money do you get if you vacuum 24 rooms?

p=5(24)-52

p=120-52

p=68