Question 131825
Start by actually writing out every equation that you can deduce from the problem statement. 

"A rectangle is 5 feet longer than it is wide." 
{{{L = 5 + W}}} 

"The perimeter of the rectangle is 34 feet." 
{{{2L + 2W = 34}}} 

What is the length of the rectangle? 
L = ? 

Substitute the first equation into the second equation, obtaining: 
{{{2(5+W) + 2W = 34}}} 

Distributing: {{{10+2W + 2W = 34}}} 
Combining like terms: {{{10 + 4W = 34}}} 
Subtracting 10 from both sides: {{{4W = 24}}} 
Dividing both sides by 4: {{{W = 6}}} 
If W = 6, then L = 11 since {{{L = 5 + W}}} as stated earlier. 

-ntnk