Answer:
<h2>All four interior edges are 4 inches, 3 inches, 4 inches and 3 inches.</h2>
Step-by-step explanation:
Givens
- The area of the frame is 18 square inches.
- The wide of the frame is 1 inch.
- One of the outer edges of the fram is 5 inches long.
If one side is 5 inches long and the wide is 1 inch, then the inner side is 3 inches long, becase we must subtract the 2 inches of the wide.
The image attached shows all relations we need to make regarding both areas.
The inner area is defined as
![A_{inner}=(b-2)3](https://tex.z-dn.net/?f=A_%7Binner%7D%3D%28b-2%293)
The area of the whole
![A_{whole}=5b](https://tex.z-dn.net/?f=A_%7Bwhole%7D%3D5b)
The area of the frame is defined as the difference of the inner area and the whole area
![A_{frame}=A_{whole}-A_{inner}\\ 18=5b-3(b-2)](https://tex.z-dn.net/?f=A_%7Bframe%7D%3DA_%7Bwhole%7D-A_%7Binner%7D%5C%5C%20%2018%3D5b-3%28b-2%29)
Now, we solve for ![b](https://tex.z-dn.net/?f=b)
![18=5b-3(b-2)\\18=5b-3b+6\\18-6=2b\\b=\frac{12}{2}\\ b=6](https://tex.z-dn.net/?f=18%3D5b-3%28b-2%29%5C%5C18%3D5b-3b%2B6%5C%5C18-6%3D2b%5C%5Cb%3D%5Cfrac%7B12%7D%7B2%7D%5C%5C%20b%3D6)
The interior each is defined as b-2, so its length is
![b-2=6-2=4](https://tex.z-dn.net/?f=b-2%3D6-2%3D4)
Therefore, the interior edges are 4 inches and 3 inches long.
All four interior edges are 4 inches, 3 inches, 4 inches and 3 inches.