Answer:
3.
![x^2-10x+25=0](https://img.qammunity.org/2020/formulas/mathematics/middle-school/nt5tcjrn03hf9ijmunqug0gr2tlpkoktp5.png)
Explanation:
All the polynomials in the given option are quadratic.
By the fundamental theorem of algebra, the quadratic polynomial has two roots.
Since the solution set is given as {5}, the quadratic has a repeated root.
In other words the root has a multiplicity of 2.
Hence we have the equation:
, multiplicity 2
This implies that;
![(x-5)^2=0](https://img.qammunity.org/2020/formulas/mathematics/middle-school/prwl2lcv2f3iwmszvzwx2wjz9po36jjhq0.png)
We expand to obtain;
![x^2-5x-5x+25=0](https://img.qammunity.org/2020/formulas/mathematics/middle-school/5kt32rc43ac39s5vzuyazwxks5nsie9ird.png)
![x^2-10x+25=0](https://img.qammunity.org/2020/formulas/mathematics/middle-school/nt5tcjrn03hf9ijmunqug0gr2tlpkoktp5.png)
The correct choice is the third option.