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### Finding Your Position on a Football Field

```
Date: 11/1/95 at 15:31:22
From: Navigator
Subject: help on a function

Suppose you start at the goal line of a football field and walk
toward the other goal line.  After you have walked x yards, you
will be on the  F(x) yard-line. For example, after you walk 60
yards you are on the 40 yard line.  Write a function F(x) that
represents your position on the football field after walking x
yards from the goal line. Give the domain of this function and the

Could you please assist me on this problem.  Your help is greatly
appreciated.

John Reichel  102344.1331@compuserve.com
```

```
Date: 11/3/95 at 14:57:30
From: Doctor Ken
Subject: Re: help on a function

Hello!

Here's a hint that may help you solve this problem.  Try using the
"absolute value" function.  It's defined by Abs(x) = Sqrt{x^2}.
Its graph looks like this:

^
|
|
\          |          /
\         |         /
\        |        /
\       |       /
\      |      /
\     |     /
\    |    /
\   |   /
\  |  /
\ | /
\|/
-----------------------------|--------------------------->
|                     x-axis
|
|
|
|
|
|
|
|y-axis

Where the v actually goes off at 45 degree angles to the x- and y-
axes.

Good luck!

-Doctor Ken,  The Geometry Forum

```
Associated Topics:
High School Basic Algebra

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