Hello!
The answer is:
The last option,
![x^(2)-6x+9](https://img.qammunity.org/2020/formulas/mathematics/middle-school/9el4mfpeia5e7ki4vvu3gb6t0u6ibgd9ff.png)
Why?
The area of square is given by the following formula:
![Area=l*l=l^(2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/10jij9oa9lmib04uk5kcjmpx67v7yfhnv1.png)
Where, l is the side of the square, remember that a square has equal sides.
To solve the problem, we must remember the following notable product:
![(a-b)^(2)=a^(2)-2ab+b^(2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/aspww4l7aabe9tbhlqep4v7v5r7zda2yjr.png)
So, if the side of the given circle is (x-3), the area will be:
![Area=l^(2)=(x-3)^(2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/1rhw1y6z6ljcrus9o7yni2xmm9cbpl36i0.png)
Applying the notable product, we have:
![Area=(x-3)^(2)=x^(2) -(2)*(x)(3)+(-3)^(2)\\\\Area=x^(2) -(2)*(x)(3)+(-3)^(2)=x^(2)-6x+9](https://img.qammunity.org/2020/formulas/mathematics/middle-school/tknvogtnwhwqqynn772oew88kn1uo6hi1p.png)
So, the correct option is the last option:
![x^(2)-6x+9](https://img.qammunity.org/2020/formulas/mathematics/middle-school/9el4mfpeia5e7ki4vvu3gb6t0u6ibgd9ff.png)
Have a nice day!