Math Help for Section 3.6, Page 149

Example 8: Tip
The solution set in set notation is $\{x|x\le16\}$.

Example 8: Check
The solution was found to be $x\le16$, so check that
the original statement of the problem is satisfied when the width is 16
inches, but not when the width is 17 inches.

When the width is 16 inches, the girth is $4(16)=64$ inches
and the combined length and girth is

   
$\text{Length}+\text{Girth}=68+64=132\text{
inches}.$      
 Solution checks. ✓

When the width is 17 inches, the girth is $4(17)=68$ inches
and the combined length and girth is

   
$\text{Length}+\text{Girth}=68+68=136\text{
inches}.$      
 Solution does not check. ✗