What is an expression using function notation?

An equation involving x and y, which is also a function, can be written in the form y = “some expression involving x”; that is, y = f ( x). This last expression is read as “ y equals f of x” and means that y is a function of x.

Step-by-step explanation:

f(x)=3x+9  where x=-5

f(d)=8d-2  where d=3

Anything where f of something equals something is function notation

I hope this is what you wanted:

$30.32

step-by-step explanation:

65.00*.12=2.80

65.00-2.80=57.20

57.20*1.06=60.632

60.632/2=30.316