Answer:
Explanation:
Area of rectangles
The area of a rectangle of dimensions x and y is
![A=xy](https://img.qammunity.org/2020/formulas/mathematics/middle-school/92fnf84e6el1b8awjzmjadlyo48pjjzxuy.png)
The picture frame measures x and x-2 inches. The picture opening measures (x - 1) by (x + 1) inches. The external area of the frame is
![A_e=(x)(x-2)=x^2-2x](https://img.qammunity.org/2020/formulas/mathematics/middle-school/4zx1pegyiko416cqbqfnfl2t5uweg3bavc.png)
The area of the picture opening is
![A_o=(x-1)(x+1)=x^2-1](https://img.qammunity.org/2020/formulas/mathematics/middle-school/6qa9u7rmdasbkwx6f4mv1re21ljjoz7yfi.png)
The ares of the frame, not including the picture opening is the difference
![A(x)=A_e-A_o=x^2-2x-(x^2-1)=-2x+1](https://img.qammunity.org/2020/formulas/mathematics/middle-school/hbgw55hm398n4xtzs59t6kmiiq4xp87t3d.png)
![A(x)=-2x+1\ inches](https://img.qammunity.org/2020/formulas/mathematics/middle-school/1ptdranl42kkbtkdkyfhc7ui8cp6uj3dzd.png)