Question 405405
You know that the perimeter of a rectangle is all of its sides added together. 
Let's have the width be "w" and the length be "2w+8", as it's eight more than twice the width. 
Now, there are two lengths(2w+8) and two widths(w) in a rectangle, so if you add them together that gives you the perimeter. 
Just put your values into an equation.
(w)+(w)+(2w+8)+(2w+8)=46
6w+16=46
6w=30
Divide by both sides. 
w=5
Your width is 5 and your length is 2w+8, so 10+8, 18. 
Hope this helps!