4.8 Problem Solving Help
Help for Exercises 46-53 on page 256
In Exercises 46-49, the ordered pairs are written in function notation. For example, f (-4) = 6 can be thought of as the ordered pair (-4, 6). Once you identify the two ordered pairs given, you can apply the formula to find the slope of the linear function. Recall that in Lesson 4.5 you learned how to use this formula to find the slope of a line using the coordinates of any two points on the line. Refer to pages 229-232 if you need help remembering how to do this.
In Exercises 50-53, start by recalling the definition of a function. A function is defined as a relation where each value of the domain (input) is paired with exactly one value in the range (output). To find out whether each input has exactly one output, you can re-write each set of ordered pairs as an input-output diagram like the ones shown in Example 1 on page 252, or Exercises 7, 8, 13, 14, and 15 on page 255. If an input has more than one output, the relation is not a function.