### Home > PC3 > Chapter 3 > Lesson 3.2.4 > Problem 3-135

3-135.

Consider the values on the

*‑axis and their corresponding subscript values as shown at right.*

Write a linear equation for

.Write the equation of a linear function using the points

and . Express

in sigma notation. Use your answer to part (a), making sure your stating index is

. For some function,

, expressin sigma notation.This is similar to your answer to part (b), but using function notation.

How are parts (a), (b), and (c) related?